Laser-induced carbon nanostructures

Abstract

A method for producing carbon nanostructures, such as carbon foam materials, is disclosed. The method includes (a) using a first laser beam to irradiate an encapsulated or sub-surface region of a carbon precursor material below the surface of the material to create carbon foam at the sub-surface region and disordered amorphous non-graphene material above the carbon foam, and then (b) using a second laser beam to remove or ablate the disordered amorphous non-graphene material above the carbon foam to expose at least a portion of the carbon foam. The resulting carbon foam material exhibits a prominent D peak, a 2D peak that is significantly smaller than the G peak, and a peak D:peak G ratio significantly greater than zero. In appearance and Raman signature, the carbon foam appears similar to carbon nano-onion material. The carbon foam can be used in biosensors, supercapacitors, and pseudocapacitors.

Description

[Technical field]

[0001] The present invention relates to laser-induced generation of carbon nanostructures, including turbostratic twisted multilayer carbon foams. [Background technology]

[0002] Carbon nanostructures are both fascinating and the subject of intensive research. Carbon nano-onions, also known as multi-layer fullerenes, are an example of this. See "Raman spectroscopy of polyhedral carbon nano-onions", DOI: 10.1007 / s00339-015-9315-9 and further "Carbon nano-onions: unique carbon nano-structures with fascinating properties and their potential applications", DOI: 10.1016 / j.ica.2017.07.021, the contents of which are incorporated by reference.

[0003] Graphene, another carbon nanostructure, has been of interest for many years for applications including biosensors, electrochemical sensing systems, supercapacitors, electrodes, and fuel cells. Known methods for producing 3D graphene include laser-induced graphene production, described in WO2019 / 038558. When a suitable carbon precursor material, such as a polyimide film, is positioned on a supporting substrate and irradiated with a CO2 laser, 3D graphene is formed on the exposed surface of the polyimide film. Experience has shown that the thickness of 3D graphene produced by this method is less than 50 μm, and furthermore, the 3D graphene itself is brittle and can adhere poorly to the underlying substrate and can peel off from it. Therefore, 3D graphene is not suitable for many applications.

[0004] A note on the terminology used in the field of carbon nanostructures: Taking just the term "graphene", there are many different forms of "graphene", for example the literature describes monolayer graphene, bilayer graphene, turbostratic graphene, graphene superlattices, graphene fibers, 3D graphene, graphene aerogels, wrinkled graphene, and many other forms. This presents a definitional challenge, since the use of a particular term (e.g., "3D graphene") may imply a limitation to only that particular form of graphene. Furthermore, IUPAC (International Union for Pure and Applied Chemistry) recommends using the name "graphite" for this three-dimensional material, and "graphene" only when the reactions, structural relationships, or other properties of the individual layers are discussed.

[0005] Therefore, the term "carbon foam" is used herein as a generalized term and should be interpreted broadly to cover any carbon nanostructure such as 3D carbon material foams, including turbostratic twisted multilayer 3D carbon material foams.

[0006] One instance of the term "carbon foam" refers to a material produced using the methods described herein, which has somewhat different properties than conventional graphene or conventional graphene foam. For example, graphene foam has several properties: it is hydrophobic and has low wettability. Raman analysis of a typical graphene foam reveals the following signatures: absence of D peak, 2D peak higher than G peak, and a peak D:peak G ratio close to zero. As described in more detail below, carbon foam produced in implementations of the present invention does not share any of these characteristics, it is hydrophilic with a contact angle of less than 20°, it lacks the characteristic Raman signature of graphene, it shows a prominent D peak, the 2D peak is significantly smaller than the G peak, and the peak D:peak G ratio is significantly above zero. In appearance and Raman signature, the carbon foam appears closer to a carbon nano-onion material. The term "carbon foam" therefore also includes within its scope materials that are carbonaceous nanostructures, such as carbon nano-onions, carbon nanohorns, carbon nanotubes, carbon nanodots, nanodiamonds, and fullerenes, or any combination thereof. Summary of the Invention

[0007] Described herein is an approach in which the surface of the carbon precursor is not converted to graphene at all, but instead sub-surface or encapsulated regions of the carbon precursor are converted to carbon foam by a focused laser beam.

[0008] The present invention is defined as in claim 1, namely a method for producing a carbon foam material, comprising the steps of: (a) using a first laser beam to irradiate an encapsulated or sub-surface region of a carbon precursor material below a surface of the material to produce carbon foam in the sub-surface region and disordered amorphous non-graphene material on the carbon foam; and then (b) using a second laser beam to remove or ablate the disordered amorphous non-graphene material overlying the carbon foam to expose at least a portion of the carbon foam.

[0009] The amorphous non-graphene material is "above" the carbon foam in that it is closer to the laser generating the laser beam than the carbon foam. One implementation of the present invention is described as a "dual laser" process because two separate lasers are used to generate the carbon foam material. The carbon foam material exhibits a prominent D peak, a 2D peak that is significantly smaller than the G peak, and a peak D:peak G ratio significantly above zero. In appearance and Raman signature, this carbon foam appears similar to carbon nano-onion material. This carbon foam can be used in biosensors, supercapacitors, and pseudocapacitors. In one implementation, the carbon foam is referred to as "Gii" carbon foam. [Brief description of the drawings]

[0010] The present invention will now be described with reference to implementations of the invention illustrated in the following figures.

[0011] [Figure 1] Schematic showing the dual laser process used to create carbon foam when a polyimide (PI) film, which serves as a carbon precursor, is positioned on a substrate. [Diagram 2] Schematic showing the dual laser process used to create carbon foam when a polyimide (PI) film, which serves as a carbon precursor, is positioned on a substrate. [Diagram 3] Schematic showing the dual laser process used to create carbon foam when a polyimide (PI) film, which serves as a carbon precursor, is positioned on a substrate. [Figure 4] Schematic showing the dual laser process used to create carbon foam when a polyimide (PI) film, which serves as a carbon precursor, is positioned on a substrate. [Diagram 5] Schematic showing the dual laser process used to create carbon foam when a polyimide (PI) film, which serves as a carbon precursor, is positioned on a substrate. [Figure 6] Schematic showing the dual laser process used to create carbon foam when a polyimide (PI) film, which serves as a carbon precursor, is positioned on a substrate. [Figure 7] Scanning electron image (×250) showing the unique surface morphology of carbon foam achieved using the dual laser method. [Figure 8] Scanning electron image showing the surface of conventional laser-induced graphene. [Figure 9] FIG. 13 shows a schematic of the dual laser process used to create carbon foam when no PI film is located on the substrate to serve as the carbon precursor. [Figure 10] FIG. 13 shows a schematic of the dual laser process used to create carbon foam when no PI film is located on the substrate to serve as the carbon precursor. [Figure 11] FIG. 13 shows a schematic of the dual laser process used to create carbon foam when no PI film is located on the substrate to serve as the carbon precursor. [Figure 12] FIG. 13 shows a schematic of the dual laser process used to create carbon foam when no PI film is located on the substrate to serve as the carbon precursor. [Figure 13] FIG. 13 shows a schematic of the dual laser process used to create carbon foam when no PI film is located on the substrate to serve as the carbon precursor. [Figure 14A] FIG. 13 shows a schematic of the dual laser process used to create carbon foam when no PI film is located on the substrate to serve as the carbon precursor. [Figure 14B]FIG. 13 shows a schematic of the dual laser process used to create carbon foam when no PI film is located on the substrate to serve as the carbon precursor. [Figure 15] Cyclic voltammography (CV) graphs of carbon foam electrodes produced using the dual laser method. [Figure 16] Figure 16A: Graph showing peak separation ΔEp as a function of scan rate for carbon foam electrodes produced using the dual laser method. Figure 16B: Graph showing peak separation ΔEp as a function of scan rate for conventionally produced graphene electrodes. [Figure 17] Comparison of electrochemical impedance spectroscopy results for carbon foam electrodes produced using the dual laser method and also conventionally produced graphene electrodes. [Figure 18] Figures 18A and B: Raman analysis of carbon foam samples made by the dual laser process. Figure 18C: Raman analysis of carbon nano-onion material. [Figure 19] Scanning electron image showing dual laser carbon foam and conventional graphene. [Figure 20] Schematic image of a biosensor including dual laser carbon foam (this implementation of carbon foam is called Gii-Sens). [Figure 21] FIG. 2 is a detailed process flow chart of the dual laser carbon foam (referred to as Gii-Sens, Gii-Sens+, and PPC Gii-Sens variants). [Figure 22] FIG. 2 is a detailed process flow chart of the dual laser carbon foam (referred to as Gii-Sens, Gii-Sens+, and PPC Gii-Sens variants). [Figure 23] FIG. 2 is a detailed process flow chart of the dual laser carbon foam (referred to as Gii-Sens, Gii-Sens+, and PPC Gii-Sens variants). [Figure 24] Schematic image of a supercapacitor containing dual-laser carbon foam (this implementation of carbon foam is called Gii-Cap). [Diagram 25] Schematic image of a supercapacitor containing dual-laser carbon foam (this implementation of carbon foam is called Gii-Cap). [Figure 26] Schematic image of a supercapacitor containing dual-laser carbon foam (this implementation of carbon foam is called Gii-Cap). [Figure 27] Schematic image of a supercapacitor containing dual-laser carbon foam (this implementation of carbon foam is called Gii-Cap). [Figure 28] FIG. 1 is a detailed process flow chart for dual laser carbon foam (referred to as Gii-Cap and Gii-Cap+ variants). [Figure 29] FIG. 1 is a detailed process flow chart for dual laser carbon foam (referred to as Gii-Cap and Gii-Cap+ variants). [Diagram 30] Schematic cross-section through an integrated lab-on-a-chip (LoC) device including a biosensor and a supercapacitor made using dual laser carbon foam. [Diagram 31] Exploded view of the fully integrated LoC device. [Diagram 32] 1 shows a LoC device that displays quantitative results on a display of the LoC device. [Diagram 33] An exploded view of an environmental monitoring device that includes a Gii-Sens sensor. [Diagram 34] Diagram of the assembled environmental monitoring device. [Diagram 35] FIG. 14 is a schematic cross-section through a device comprising a battery (e.g., a printed battery or a conventional battery) and also a Gii-Cap supercapacitor. [Diagram 36] FIG. 1 is a schematic diagram of a smart label, which comprises a battery (eg, a printed battery or a conventional battery) and also a Gii-Cap supercapacitor. [Figure 37] FIG. 2: Schematic cross-section showing the basic layering of different materials in the Gii-Thru variant, a three-dimensional structure of carbon foam. [Figure 38] Schematic diagram of various Gii-Thru Gii-Cap / Gii-Cap+ three-dimensional supercapacitor devices. [Figure 39] Schematic diagram of various Gii-Thru Gii-Cap / Gii-Cap+ three-dimensional supercapacitor devices. [Diagram 40] Schematic diagram of various Gii-Thru Gii-Cap / Gii-Cap+ three-dimensional supercapacitor devices. [Diagram 41] Schematic diagram of various Gii-Thru Gii-Cap / Gii-Cap+ three-dimensional supercapacitor devices. [Diagram 42] Schematic diagram of various Gii-Thru Gii-Cap / Gii-Cap+ three-dimensional supercapacitor devices. [Figure 43A] Detailed process flow chart for dual laser carbon foam Gii-Thru Cap three-dimensional supercapacitor device. [Figure 43B] Detailed process flow chart for dual laser carbon foam Gii-Thru Cap three-dimensional supercapacitor device. [Figure 44A] Schematic diagram of the Gii-Thru sensor used in the three-sample array microfluidic diagnostic device. [Figure 44B] Schematic diagram of the Gii-Thru sensor used in the three-sample array microfluidic diagnostic device. [Figure 45A] Schematic diagram of the Gii-Thru sensor used in the eight-sample array microfluidic diagnostic device. [Figure 45B] Schematic diagram of the Gii-Thru sensor used in the eight-sample array microfluidic diagnostic device. [Figure 46A] FIG. 1 shows a perspective view of a fully assembled multi-sample array microfluidic diagnostic device. [Figure 46B] An overhead view of the multi-sample array microfluidic diagnostic device. [Figure 47] Diagram of a microfluidic diagnostic device. [Figure 48]Diagram of a microfluidic diagnostic device. [Figure 49] Detailed manufacturing process flow for high sensitivity, low cost Gii-Thru variant. [Figure 50] Schematic diagram of high speed reel-to-reel or reel-to-sheet manufacturing system for Gii carbon foam. [Figure 51] FIG. 50 shows a detailed process flow for the system. [Figure 52] Scanning electron images showing dual laser carbon foam at various magnifications. [Figure 53] Scanning electron images showing dual laser carbon foam at various magnifications. [Figure 54] Scanning electron images showing dual laser carbon foam at various magnifications. [Figure 55] Scanning electron images showing dual laser carbon foam at various magnifications. [Figure 56] Scanning electron images showing dual laser carbon foam at various magnifications. [Figure 57] Figure 57A: Scanning electron images showing dual laser carbon foam at various magnifications. Figure 57B: Scanning electron images of carbon nano-onion material made using a conventional process. [Figure 58] Figure 1 shows the Raman shift for eight sheets of carbon foam made using a dual laser process. Appendix 1. Implementation of a supercapacitor with a hydrogel electrolyte [Figure 59] A carbon foam cyclic voltammogram is presented for positive voltage measured at 25 mV / sec. [Figure 60] 1 shows a negative voltage carbon foam cyclic voltammogram measured at 25 mV / sec. [Figure 61] 1 shows the carbon foam galvanostatic charge-discharge (GCD) curves measured at 0.5 mA / cm2 for the positive voltage window. [Figure 62] 1 shows the carbon foam galvanostatic charge-discharge (GCD) curves measured at 0.5 mA / cm2 for the negative voltage window. [Figure 63]Carbon foam galvanostatic charge-discharge (GCD) data obtained from five two-electrode devices are shown. [Figure 64] Carbon foam cyclic voltammograms recorded from five different two-electrode devices at high (left) and low (right) scan rates are shown. [Figure 65] Carbon foam cyclic voltammogram data are shown for five additional systems that differ by the nature of the hydrogel electrolyte: (a) 3 M NaClO4 and PVA, (b) 1 M NaClO4 and PVA, (c) 2.5 M NaNO3 and PVA, (d) 3 M Mg(ClO4)2 and PVA, and (e) 5 M NaClO4 and PVP. Appendix 2: Gii-Cap+Hydrogel [Figure 66] A typical CV curve for the Gii-Cap+ hydrogel device. [Figure 67] Typical GCD curves for Gii-Cap+ hydrogel devices after conditioning. [Figure 68] Post-conditioning Nyquist (left) and Bode (right) plots for the Gii-Cap+ device are shown. Appendix 3 GiiCap Ion Gel [Figure 69] Results for the GiiCap ion gel device. [Figure 70] Results for the GiiCap ion gel device. [Figure 71] Results for the GiiCap ion gel device. [Figure 72] Results for the GiiCap ion gel device. [Figure 73] Results for the GiiCap ion gel device. [Figure 74] Results for the GiiCap ion gel device. Appendix 4. Proposed 3-month Gii-Sens assay feasibility [Figure 75] Schematic of the assay procedure for the Gii-Sens 3D carbon foam assay system. [Figure 76]Schematic of the assay procedure for the Gii-Sens 3D carbon foam assay system. [Figure 77] Schematic of the assay procedure for the Gii-Sens 3D carbon foam assay system. [Figure 78] Schematic of the assay procedure for the Gii-Sens 3D carbon foam assay system. [Figure 79] 1 shows the surface chemistry for Gii-Sens 3D carbon foam. [Figure 80] 1 shows the surface chemistry for Gii-Sens 3D carbon foam. [Figure 81] 1 shows the surface chemistry for Gii-Sens 3D carbon foam. [Figure 82] 1 shows label-free assay probing for Gii-Sens 3D carbon foam. [Figure 83] Label-free assay probing for Gii-Sens 3D carbon foam is shown. Appendix 6 Benchmark experimental conditions [Figure 84] Performance of Gii-Sens carbon foam compared to graphene electrode materials. [Figure 85] Performance of Gii-Sens carbon foam compared to graphene electrode materials. [Figure 86] Performance of Gii-Sens carbon foam compared to graphene electrode materials. [Figure 87] A graph comparing the performance of Gii-Sens carbon foam with carbon-based electrode materials. [Figure 88] A graph comparing the performance of Gii-Sens carbon foam with carbon-based electrode materials. [Figure 89] A graph comparing the performance of Gii-Sens carbon foam with carbon-based electrode materials. [Figure 90] A graph comparing the performance of Gii-Sens carbon foam to screen printed gold. [Figure 91] A graph comparing the performance of Gii-Sens carbon foam to screen printed gold. [Figure 92]Graph comparing the performance of Gii-Sens carbon foam with screen printed gold. Appendix 7: Optimization of surface immobilization of anti-human procalcitonin (cAb) [Figure 93] A direct assay procedure for optimization of surface immobilization of anti-human procalcitonin (cAb) is presented. [Figure 94] Schematic of the surface immobilization reaction. [Figure 95] 4 shows the Rct and ΔEp signal responses for NHS functionalization of a Gii-Sens electrode. [Figure 96] 1 shows cAb immobilization on a GiiSens electrode. [Figure 97] Shown is the signal response from 2000 pg / ml in the direct assay format using 100 μg / ml of cAb surface coating.

[0012] It should be noted that Gii, Gii-Sens, Gii-Sens+, Gii-Cap, Gii-Cap+, Gii-Thru, and PPC Gii are trademarks of the patent owners. "Gii" generally refers to carbon foam made using a dual laser process. "Gii-Sens" refers to Gii carbon foam used in sensors such as biosensors. "Gii-Cap" refers to Gii carbon foam used in supercapacitors. The + suffix refers to Gii carbon foam when modified with a metal oxide layer or film. "Gii-Thru" refers to Gii carbon foam when arranged in a specific three-dimensional structure. "PPC" refers to "post-print conversion", a specific manufacturing process in which Gii carbon foam is created after various screen printing steps are completed.

[0013] Figure Index Dual Laser Process 11 IR Laser 12 IR laser beam 13 Inside the PI film 14 PI film 15 Base material 16 Sub-surface carbon foam region 17 Disordered amorphous non-graphene material beneath the subsurface carbon foam region 18. Extended regions of disordered amorphous non-graphene material above the subsurface carbon foam region 20 CO2 Laser 21 Unique surface morphology of exposed carbon foam regions Biosensors 201 Polyimide substrate 202 Carbon foam working electrode 203 Carbon foam counter electrode 204 Carbon foam reference electrode 205 Screen printed silver interconnects 206 Dielectric layer 207 Area where silver connection wiring path overlaps with electrode Gii-Cap Supercapacitor 241 Array of Carbon Foam Electrodes 242 Screen printed silver connectors 243 Dielectric Layer 244 Polyimide base layer 245 Copper Connection Tab 246 Electrolyte layer 247 Aluminum Laminated Heat Seal Pouch 250 Carbon Foam Digit Rounded Edges Combined Sensor and Supercapacitor 301 Upper polyimide layer 302 Gii-Sens Biosensor 303 Lower polyimide layer 304 Supercapacitor 305 Plastic Pieces 306 Microchannel 307 Connector Wiring 308 Flexible electronic devices 310 Inductive Power Loop 312 Gii-Cap Supercapacitor 313 Gii-Sens Biosensor 314 Device layer with microelectronic devices 315 Top Panel 316 Display 317 Circular Analyte Well Environmental Monitoring 330 Gii-Sens Carbon Foam Sensor 331 Control Electronics 332 PV Solar Cell 333 Gii-Cap Carbon Foam Supercapacitor 334 Detachable back Combined Supercapacitor and Battery 351 First polyimide layer 352 Supercapacitor 353 Second polyimide layer 354 Batteries 355 BMS (Battery Management System) 356 Flexible electronic devices 357 Electrical Connections Smart Label 360 flexible battery 361 Supercapacitor 362 Electronics Module 363 Exposed Label Surface 364 Adhesive Release Liner 364 Gii-Thru Cap 371 PI Film 372 Screen-printed conductive ink or conductive paste layer 373 Screen Printed Collector 374 Dielectric Insulators 375 Encapsulated Carbon Foam Layer 376 Disordered amorphous non-graphene layer beneath a carbon foam layer 377 Unique surface morphology layer 390 Hydrogel electrolyte layer 391 Carbon foam layer with unique surface morphology 392 PI Film 393 Screen-printed carbon paste layer 394 Screen printed silver connector layer 395 Copper Tab for Silver Connector Layer 396 Distributed Dielectric Isolation Layer 397 Second carbon foam layer with unique surface morphology 398 PI Film 399 Hydrogel Electrolyte Layer 400 Dielectric isolation layer 401 Screen printed silver collector layer 402 Copper tab 403 Screen printed carbon paste layer 404 Carbon foam layer 405 PI film Gii-Thru Sens 3. Spot Array Microfluidic Diagnostic Device 440 Analyte Sample Wells 441 Stacked well spacer layers 442 Polyimide film 443 Screen-printed conductive carbon layer 444A Reference electrode connection 444B Working electrode connection 444C Counter electrode connection 447 Screen printed dielectric layer 448A Reference Electrode 448B Working electrode 448C Counter electrode 449 Screen-printed carbon layer of reference electrode 8 Spot Array Microfluidic Diagnostic Device 451 Stacked Well Spacers 452 Array of 8 analyte wells 453 Well for counter electrode 454 Well for reference electrode 455 Polyimide layer 456 Polyimide layer 457 8 working electrodes 458 Counter Electrode 459 Reference electrode 460 Screen printed carbon connection interface layer 461 Screen printed silver interconnects 462 Screen printed dielectric layer 470 Top Microfluidic Foil 471 Interlayer Microfluidic Foil 472 Printed or molded microfluidic channels 473 Bottom microfluidic foil with adhesive 474 Gii-Thru Sensor 475 Connector 481 Transparent resin barb connector 482 Top Wheel 483 Transparent resin molded microfluidic card 484 Microfluidic Channels 485 Well Unit 486 Gii-Thru Sensor DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] We begin with a simplified schematic step-by-step description of an implementation of the invention. Two step-by-step descriptions are provided. The first one (FIGS. 1-6) describes at a high level the carbon foam production process when a carbon precursor (e.g., a polyimide (PI) film, such as a Kapton® film, in this case) is attached onto a substrate, while the second step-by-step description (FIGS. 9-14) covers the carbon foam production process when no polyimide film is attached onto a substrate. In each case, a dual laser process is used, and the meaning of this term is explained below.

[0015] In a first step (see FIG. 1), a laser 11 having a wavelength A irradiates with a laser beam 12 an interior 13 of a polyimide film 14 that is positioned on a substrate 15 suitable for the intended application. The laser can be a pulsed IR laser delivering IR radiation having a wavelength of 1064 nm.

[0016] As shown in FIG. 2, a laser 11 having a wavelength A is adjusted so that the sub-surface region 16 is converted to carbon foam. The focus of laser A is moved gradually through the interior 13 of the polyimide film 14 to create the entire carbon foam region 16. The carbon foam region 16 can be about 50 μm or more in depth or height, much higher than would be possible otherwise. Note that the exposed surface of the polyimide film 14 (i.e., the surface on which the laser beam is incident) does not always have carbon foam created. The region above the carbon foam 16 (i.e., closer to the laser than the carbon foam region 16) is not converted to carbon foam. The region 17 below the carbon foam region 16 (i.e., the underside of the PI film) is also not converted to carbon foam, but instead is converted to a disordered amorphous non-graphene material that adheres to the underlying substrate 15.

[0017] 3 shows that a laser 11 having a wavelength A causes a physical expansion in a region 18 above the interior carbon foam zone 16 (i.e., closer to the laser than the carbon foam region 16) due to trapped gas. This region 18 is neither 3D graphene nor a polymer, but rather a disordered amorphous material.

[0018] In a second step, as shown in Figure 4, a laser 20, now having a wavelength B, is modulated on the disordered amorphous material region 18 above the carbon foam region 16. This can be a CO2 laser with a wavelength of 10.6 µm.

[0019] As shown in FIG. 5, this laser 20 having a wavelength B ablates some or all of the region 18 above the carbon foam region 16, exposing at least a portion of the underlying carbon foam region 16.

[0020] Also, as shown in FIG. 6, a laser 20 having wavelength B also imparts a unique surface morphology 21 to the underlying carbon foam region.

[0021] The process described in FIGS. 1 to 6 is referred to as the "dual laser process."

[0022] Figure 7 is a scanning electron image (x250) showing the unique surface morphology achieved using the dual laser method. In this case, the carbon source was first irradiated with 1064 nm wavelength IR radiation from a pulsed IR laser, the radiation was focused on the carbon source and irradiated at progressive depths within the carbon source, and then the carbon source was irradiated with a 10.6 μm wavelength laser beam from a CO2 laser. The approximate thickness of the carbon foam layer in this image is 220 μm.

[0023] The contrast with the surface morphology achieved using conventional LIG methods, shown in Figure 8 (x250), is clear: there are clear raster lines and the folds are less intertwined. The thickness of this carbon foam layer is less than 50 μm.

[0024] From the images in Figure 7, it can be inferred that the material created using the dual laser process does not have a similar surface morphology as conventional graphene foam; the material appears to be a turbostratic twisted multilayer 3D carbon-based material with a foam-like structure, but it is not necessarily what would normally be described as "graphene" in the conventional sense. Further details are provided in Feature R below.

[0025] In the previous step-by-step description (Figures 1-6), we considered the dual laser process when the carbon precursor material (polyimide film) is mounted on a substrate. In the following Figures 9-14, we consider the dual laser process when the polyimide film is not mounted on a substrate. The manufacturing process, which will be described in detail later for two implementations called Gii-Cap (supercapacitor) and Gii-Sens (sensor), uses a standard 220 mm x 180 mm polyimide film sheet that is not mounted on a substrate, and this size can be accommodated in a standard laser scanning device of the kind typically used for laser engraving, laser cutting, and laser plotting that traces a path defined by a standard CAD program. This manufacturing process also uses a standard flatbed screen printing device, and a standard conveyor dryer, and is easily compatible with stacking thin PI films of various sizes. Other sizes of polyimide sheets can be accommodated.

[0026] As previously mentioned, a laser 11 (e.g., an IR laser) having wavelength A irradiates the interior 13 of the PI film 14, which is now unmounted on a substrate, as shown in Figure 9. The film 14 can be supported at its edges, or temporarily placed on a surface, or it can be a sheet forming part of a reel of PI film when a continuous manufacturing (e.g., reel-to-reel or reel-to-sheet) system is used (see feature P below).

[0027] As shown in Figure 10, a laser 11 having a wavelength A is tuned so that a sub-surface region 16 is converted to carbon foam. The focal point is moved progressively through the film 14 to create the entire carbon foam region 16. The carbon foam region 16 can be about 50 μm or more in height, much deeper or taller than would otherwise be possible.

[0028] 3D graphene does not always form on the exposed surface of the polymer film: the upper regions of the carbon foam do not convert to 3D graphene.

[0029] As shown in Figure 11, there is a physical expansion of region 18 above the inner carbon foam zone 16 due to trapped gas. This region is neither 3D graphene nor a polymer, but a disordered amorphous material.

[0030] Now, a laser 20 (e.g., CO2) having a wavelength B is modulated on the region 18 above the carbon foam region 16, as shown in Figure 12. The laser 20 having a wavelength B ablates the region 18 above the carbon foam region 16, exposing at least a portion of the underlying carbon foam 16, as shown in Figure 13.

[0031] Similar to when the polyimide film 14 is attached onto the substrate, the laser 20 having wavelength B also imparts a unique surface morphology 21 to the underlying carbon foam 16, as shown in FIG.

[0032] Here are some implementation details for this dual laser approach to carbon foam generation: In one example, a Nd:YAG solid state laser is a laser of wavelength A and is positioned such that an IR laser radiation beam (1064 nm wavelength) generated by the solid state laser impinges on the polyimide layer perpendicular to the layer. An optical system focuses the IR laser radiation beam to a minimum beam convergence volume within the polyimide layer.

[0033] In the encapsulated or sub-surface regions or locations around the minimum beam convergence, the interaction of the laser light with the polyimide results in carbonization of the carbon source, which results in the production of carbon foams, such as twisted or turbostratic multi-layered carbon foams, in the encapsulated or sub-surface regions, and the production of a layer of disordered amorphous non-graphene material on the surface of the polyimide film.

[0034] While maintaining the laser beam focused at a particular depth within the polyimide layer, the laser is scanned laterally over the polyimide layer, thus tracing a path entirely within the polyimide carbon source and converting it into carbon foam. Thus, the polyimide is carbonized into carbon foam in a pattern corresponding to the path traced by the scanned focused IR laser beam.

[0035] In one setup, the Nd:YAG IR laser was pulsed at a frequency of 80 kHz and the laser beam was scanned across the surface at a speed of 9.4 cm / sec. Other embodiments utilized different parameters. For example, a pulse frequency of 50 kHz and a scanning speed of 35.5 cm / sec have also been used to successfully produce carbon foam. The laser power is within a typical operating range of 8-20 watts, with 12 W being optimal, and the laser focal length is within a typical operating range of 50 mm-400 mm.

[0036] When a given area in the polyimide layer is irradiated in the above manner with the focused IR laser beam, the depth of the encapsulated or subsurface regions or locations in the polyimide changes, and the IR laser beam is scanned again over an area, in this case the same given area. A standard computer-controlled laser scanning system can be used that controls the XY position of the laser on the polyimide film. To generate carbon foam, it may be necessary to make two or more passes of the focused IR laser radiation over the same area. In this implementation, the focused IR laser also irradiates adjacent but substantially non-overlapping areas. This process of irradiating the carbon source with the focused IR laser radiation at different focal depths is repeated until the desired depth of the polyimide layer is exposed to the IR laser radiation and carbon foam is formed in the encapsulated or subsurface regions. However, the surface layer is a disordered amorphous non-graphene material.

[0037] In a second step, the polyimide layer is exposed to radiation from a CO2 laser to perform an ablation process, exposing at least a portion of the underlying carbon foam and imparting a particular surface morphology to the exposed carbon foam. The radiation from the CO2 laser is scanned across the surface of the treated carbon source at a speed of 19 cm / sec to match the pattern or area illuminated with the IR laser. Other embodiments utilized different parameters. For example, a pulse frequency of 50 kHz and a scanning speed of 35.5 cm / sec were also utilized to successfully expose the underlying carbon foam. The laser power is within a typical operating range of 8-20 watts, with 12 W being optimal, and the laser focal length is within a typical operating range of 50 mm-400 mm.

[0038] As described above, the CO2 laser ablates the surface layer of disordered amorphous non-graphene material, exposing the underlying carbon foam and modifying the surface morphology of the carbon foam to produce an exposed carbon foam with more defects compared to standard laser-induced graphene, which, as described above, provides exceptionally useful properties superior to standard laser-induced graphene.

[0039] Varying the laser parameters of either or both of the lasers (e.g., IR and CO2 lasers), such as power, focus, wavelength, scan speed, etc., changes the carbon foam material properties, allowing carbon foams to be manufactured with optimized properties for various applications.

[0040] One useful property of the exposed carbon foam made by the dual laser process is its high degree of wettability; the contact angle can be less than 20° making this carbon foam hydrophilic, in contrast to conventional graphene foams that have contact angles of 70°-150° making it hydrophobic. The hydrophilic property of the carbon foam produced by the dual laser process is highly relevant to two important applications: biosensors (implementation called Gii-Sens) and supercapacitors (implementation called Gii-Cap). For biosensors, high wettability leads to the liquid being tested (e.g., liquid analyte) spreading quickly and evenly across the working electrode, leading to greater sensitivity, consistency, and speed. For supercapacitors, high wettability means that the electrolyte wets the supercapacitor electrodes better, leading to higher performance. Conventional graphene foams can be treated to make the graphene foam more wettable, but no such additional treatment steps are required for this carbon foam implementation.

[0041] Another useful property of the exposed carbon foam made by the dual laser process is its high degree of fouling resistance, which may improve the sensitivity and longevity of biosensors. Carbon foam may be useful in applications where the build-up of contaminants or residues may impair the performance or longevity of components (e.g., filters, e-cigarette heating elements, electrodes), and exposed carbon foam made by the dual laser process components may be used in the components to improve performance or longevity.

[0042] The performance of the carbon foam electrodes produced using this dual laser method has been investigated by cyclic voltammography (CV), as shown in FIG. 15. Cyclic voltametric plots of the well-characterized ferricyanide / ferrocyanide redox reaction were performed on electrodes prepared using the method described above and on electrodes prepared using the known conventional CO2 laser irradiation method. FIG. 15 shows the resulting CV plots obtained at scan rates of 10 mV / s, 25 mV / s, 50 mV / s, 75 mV / s, 100 mV / s, and 150 mV / s. Each plot shows data recorded on a carbon foam electrode produced using the current dual laser method (light lines) and a 3D graphene electrode produced using the known irradiation method with CO2 laser light (dark lines). The peak at about 0.22 V in the negative current direction corresponds to the reduction of ferricyanide to ferrocyanide, and the peak at about 0.28 V in the positive current direction corresponds to the oxidation of ferrocyanide to ferricyanide.

[0043] Apart from the prominent redox peaks, it is qualitatively clear from these graphs that the CV plots recorded using the carbon foam electrodes produced using the dual laser method disclosed herein have a more rectangular appearance than the plots recorded using 3D graphene electrodes produced by known methods. This is most evident at the high end of the voltage range (about 0.6 V) and at higher scan rates (see, for example, 100 mV / sec). This increased rectangular appearance indicates increased capacitive behavior of the electrodes prepared using the present dual laser method, reflecting the very high surface area of ​​the twisted or turbostratic multilayer carbon foam produced by this method.

[0044] It is also evident from the CV plots that the voltage separating the oxidation and reduction peaks is consistently smaller for measurements performed using the carbon foam electrode produced by the dual laser method compared to measurements performed using the 3D graphene electrode produced by conventional known methods. Peak separation ΔE as a function of scan rate for CV measurements performed using the carbon foam electrode produced according to the method of the present disclosure. p are plotted in FIG. 16(a) and for CV measurements made using 3D graphene electrodes produced according to known methods are plotted in FIG. 16(b).

[0045] The data show that ΔE p The theoretical peak separation parameter for a reversible system such as the ferricyanide / ferrocyanide reversible redox reaction is 57 mV, but in practice this is sensitive to the effect of the electrode structure on the electrochemistry. It is clear that the voltage separation of the oxidation and reduction peaks in the cyclic voltammetric plot is close to the theoretical value. This is evidence of the quality of the electrodes produced by both the known method and the dual laser method. Furthermore, the reduction in separation exemplified by the results recorded with the carbon foam electrode produced by the dual laser method indicates that the porosity of the electrodes produced in this way is improved over those produced by the conventional method.

[0046] FIG. 17 shows a comparison of electrochemical impedance spectroscopy results for a system including a carbon foam electrode (squares) produced using the dual laser method and a system including a 3D graphene electrode (circles) produced using known methods. The Bode plot shows the variation of phase angle as a function of frequency. The frequency responses of the two systems are clearly different. Specifically, the measurements recorded using the carbon foam electrode produced using the dual laser method lack the phase angle signal peak observed at about 1 kHz for the measurements recorded using the 3D graphene electrode produced using the conventional method. The response from the electrode prepared using the dual laser method shows a fast electron transfer response. The difference is a further clear illustration that the carbon foam produced by the dual laser method is distinct and distinguishable from the 3D graphene produced by the conventional method.

[0047] Further details are evident from FIG. 18A. The Raman spectrum of the carbon foam made by the dual laser process is shown in FIG. 18A and has three main peaks. In particular, the Raman spectrum at about 1344 cm -1 The D peak is characteristic of the presence of lattice defects and occurs at approximately 1577 cm -1 The G peak of sp 2 This is characteristic of carbon hybridization. Approximately 2685 cm -1 The 2D peak at 2685 cm is characteristic of a second order transition in 3D graphene, and the absence of a doublet structure here indicates the lack of planar AB stacking that would be found in multilayer 2D graphene or graphite. -1 A single Lorentz peak (67 cm -1 Fitting the D / G peak ratio (which has a full width at half maximum of 0.85) indicates that only one or a few carbon foam-like layers are present in the 3D carbon formed by the two methods. Analysis of the D / G peak ratio for the dual laser process (0.85) indicates a higher defect density compared to the conventional laser-induced graphene process using a single laser step (0.67), as shown in Table 1 below. [Table 1]

[0048] As mentioned above, Raman analysis of a typical graphene foam reveals the following signatures: absence of a D peak, 2D peak higher than the G peak, and a peak D:peak G ratio close to zero. Carbon foam produced in implementations of the present invention does not share any of these properties, it is highly hydrophilic, the contact angle is less than 20°, and it lacks the characteristic Raman signature of graphene: FIG. 18A shows the presence of a D peak, a 2D peak smaller than the G peak, and a peak D:peak G ratio greater than zero for material made by the dual laser process. FIG. 18B is another Raman analysis of carbon foam made by the dual laser process, also showing the presence of a D peak, a 2D peak smaller than the G peak, and a peak D:peak G ratio greater than zero. FIG. 18C is a Raman analysis of a carbon nano-onion material, see "Raman spectroscopy of polyhedral carbon nano-onions." DOI:10.1007 / s00339-015-9315-9 and the Raman of the carbon foam made by the dual laser process are clear. One reasonable interpretation is that the carbon foam made by the dual laser process is or includes a carbon nano-onion material. See also Figures 57A and 57B below.

[0049] Both the dual laser carbon foam and conventional graphene made by a single laser process exhibit a microporous structure, as shown in the SEM images in Figure 19. The low magnification images show clear differences in surface morphology. The single laser surface exhibits a smoother striped surface with rough edges, while the carbon foam made by the dual laser process exhibits a rough surface. Feature R below revisits this area.

[0050] Key Features This section outlines key features A-R of implementations of the present invention that define the generation of carbon foam in the dual laser manufacturing process described above, which has many advantages over traditional CVD and allows the deposition of 1 cm of approximately 50 μm thick carbon foam on the plastic substrates of Table 2 (or indeed many other types of substrates). 2 The production of can be compared. [Table 2]

[0051] Features A-R define various aspects of the carbon foam manufacturing process that is highly scalable, high yielding, highly reproducible, and easily adaptable to many different applications all using the same process. For example, dual laser carbon foam is particularly well suited for biosensors and electrochemical capacitors (e.g., supercapacitor and pseudocapacitor applications).

[0052] For biosensor applications, dual-laser carbon foam has the following advantages over conventional graphene foam: higher electron transfer rate, higher detection sensitivity, larger electrochemically active area, higher reproducibility, lower cost, higher wettability, and higher anti-fouling properties. One implementation of the biosensor is called Gii-Cap, which is described in detail below.

[0053] For supercapacitor and other electronic device applications, carbon foams have the following advantages over traditional graphene foams: larger surface area, more porous structure, higher quality, lower sheet resistance, higher wettability, and higher anti-fouling properties. One implementation of a supercapacitor is called Gii-Cap, which is also described in detail below. Features A-R are organized into four groups: Group 1: Sub-surface carbon foam Group 2: Dual Laser Processing Group 3: Products Group 4: Others This organization can be expanded as follows: Group 1: Sub-surface carbon foam Feature A: Carbon foam fabricated in the sub-surface region of carbon precursor material Feature B: Carbon foam created in encapsulated regions of carbon precursor material Feature C: A carbon foam fabricated in a region of a carbon precursor material, the region being substantially free of gas escape paths. Feature D: Amorphous non-graphene material adhered to substrate Group 2: Dual Laser Processing Feature E: Carbon foam created by laser ablation of sub-surface carbon foam regions Feature F: Non-graphene carbon foams produced by laser ablation of subsurface carbon foam regions Feature G: Dual lasers operating at different frequency bands Feature H: Electrical contacts located in carbon foam created by laser ablation of sub-surface carbon foam regions Feature I: Printing of electrical contacts on polyimide film and then creating exposed carbon foam Feature J: Toll Raceways Made with Carbon Foam Feature K: Application of primary and secondary lasers in different manufacturing facilities Group 3: Products Feature L1: Biosensor Feature L2: Scalable, low-cost fabrication of carbon foam biosensors using screen printing technology Feature L3: Addition of functional groups to biosensors in different manufacturing facilities Feature L4: Addition of functional groups to biosensors as part of the biosensor generation process Feature L5: Biosensor manufacturing using PPC: Post-print conversion Feature M1: Energy storage device Feature M2: Screen-printed layers of carbon foam supercapacitors Feature M3: Carbon Foam Supercapacitor: Common Collector Feature M4: Carbon foam supercapacitor: PPC manufacturing process Feature M5: Carbon Foam Pseudocapacitor: Metal Oxide Variant Feature M6: Carbon Foam Supercapacitors: Using Ion Gel in Low Humidity Environments Feature N1: Conductor Feature N2: Combined sensor and supercapacitor Feature N3: Combined supercapacitor and battery Feature N4: Smart Label Feature N5: Combined Supercapacitor and Antenna Feature N6: Combined energy scavenger + supercapacitor. Feature O1: 3D Carbon Foam Construction: Gii-Thru for Gii-Cap Features O2: 3D carbon foam construction: Gii-Thru stackable Gii-Cap / Gii-Cap+ Feature O3: 3D Carbon Foam Construction: Gii-Thru for Gii-Sens: HISLOC Feature O4: 3D Carbon Foam Construction: Gii-Thru for Gii-Sens: HISLOC Manufacturing Process Group 4: Others Feature P: Scalable Manufacturing of Carbon Foam: Gii3 Feature Q: Various other carbon foam applications Feature R: Non-graphene carbon foam Next, we move on to group 1. Group 1: Sub-surface carbon foam Feature A: Carbon foam fabricated in the sub-surface region of carbon precursor material

[0054] In the prior art section, previous approaches to laser-induced graphene have been described how to convert a surface layer of a carbon precursor into 3D graphene. However, the resulting 3D graphene can be somewhat brittle and may peel off from the underlying substrate, making it generally unsuitable for many practical applications; furthermore, the 3D graphene is typically relatively thin, less than 50 μm deep.

[0055] Described herein is an alternative approach in which the surface of the carbon precursor is not converted to graphene at all, but instead, only sub-surface regions of the carbon precursor 14 are converted to carbon foam 16 by the focused laser beam 12, and in one implementation, the focused IR beam 12 is applied to the interior sub-surface or encapsulated regions of the polyimide film 14 for 1 ns to 10 μs (i.e., approximately 5×10 7 ℃ / sec~2×10 12 The carbon foam 16 is then heated to a temperature above 500° C. in a very short time (° C. / sec), and this short period of intense heating is sufficient to form carbon foam 16 in the sub-surface or encapsulated region. There is no substantial gas escape path from the sub-surface or encapsulated region 16, and confining the gaseous products within the sub-surface or encapsulated region beneficially affects the structure of the carbon foam 16 formed in the sub-surface region. The formation of carbon foam 16 only in the sub-surface region was an unexpected finding and was unexpected for several reasons, including the very low absorbance of 1064 nm IR radiation by the polyimide carbon precursor material (less than 50 absorbance of radiation per cm (base 10), or a low absorbance of less than 10 of 1064 nm IR radiation).

[0056] The surface (e.g., orthogonal to the laser, the interface between the carbon precursor material facing the laser and the gas environment surrounding the carbon precursor material) expands under laser irradiation and is converted from the carbon precursor material to disordered amorphous non-graphene material 18. This disordered amorphous non-graphene material 18 forms a layer that is typically at least 1% of the total thickness of the carbon precursor material; for a 500 μm thick polyimide film, typically the top 1 μm to 10 μm is converted to disordered amorphous non-graphene material 18, and below this top layer, in the main body of the carbon precursor material, there is a region that is converted to carbon foam 16.

[0057] The thickness of this carbon foam 16 is controlled by progressively moving the focal point of the laser beam through the carbon precursor material, and using this process, unusually thick carbon foam structures can be made. Carbon foam raceways as thick as 50 μm to 200 μm (approx.) have been achieved.

[0058] When the laser irradiates a carbon film precursor material, such as a polyimide film, suspended in air (i.e., not mounted on a substrate) as shown in Figures 9-14B, after irradiation, as the material is progressively moved away, disordered amorphous non-graphene material 18 is obtained at the top surface, i.e., facing the laser, and then carbon foam regions 16. The laser beam 12 generally stays away from the bottom surface of the carbon precursor material, such that the carbon foam regions 16 are located above the carbon precursor material that has not been converted to carbon foam. When the laser approaches the bottom surface of the carbon precursor material, the carbon precursor near and at the bottom surface is converted to disordered amorphous non-graphene material.

[0059] Similarly, as shown in Figures 1-6, when a laser irradiates a carbon precursor film, such as a polyimide (PI) film mounted on a substrate, the same sequence of materials is obtained, in addition, the laser approaches the underside of the carbon precursor material, which typically resides against the substrate, and the carbon precursor near and at the underside is then converted to disordered amorphous non-graphene material 17. This disordered amorphous non-graphene material 17 adheres to the substrate 15, and the carbon foam region 16 is bonded to this disordered amorphous non-graphene material 17, resulting in the carbon foam region 16 not being directly bonded to the substrate 15 itself, but nevertheless being firmly attached to the substrate 15 via the intermediate disordered amorphous non-graphene material 17.

[0060] This approach allows for carbon foam structures that are significantly thicker than those possible using previous approaches that limit the formation of graphene foam to the surface region. Additionally, this approach allows for carbon foam structures that adhere more robustly, although not directly, to the underlying substrate. Note that with this approach, carbon foam is not produced on any surface of the carbon precursor material. Instead, carbon foam is produced only in the interior sub-surface region of the carbon precursor material.

[0061] It can be generalized as follows: 1. A method of producing a carbon foam material, comprising irradiating a sub-surface region of a carbon precursor material, wherein parameters of a laser beam are selected to create carbon foam in the sub-surface region.

[0062] Feature B: Carbon foam created in encapsulated regions of carbon precursor material In feature A above, the region where the carbon foam was created by laser irradiation was defined as the "sub-surface" region. Another way to describe this region is to consider it as "encapsulated," which captures the three-dimensional relationship of the carbon foam to its surroundings, where the carbon foam 16 is "encapsulated" by the original carbon precursor material and by the disordered amorphous non-graphene material 18 created by laser irradiation on top of the carbon precursor material 14.

[0063] It can be generalized as follows: 1. A method of producing a carbon foam material, comprising irradiating an encapsulated region of a carbon precursor material, wherein parameters of a laser beam are selected to create carbon foam in the encapsulated region.

[0064] Feature C: A carbon foam fabricated in a region of a carbon precursor material, the region being substantially free of gas escape paths. It has been determined above that the sub-surface or encapsulated region of the carbon precursor is converted to carbon foam, there is no substantial gas escape path from this sub-surface or encapsulated region, and confining the gaseous products within the sub-surface or encapsulated region beneficially affects the structure of the carbon foam 16 formed in that region.

[0065] It can be generalized as follows: 1. A method for producing a carbon foam material, comprising irradiating an encapsulated sub-surface region of a carbon precursor material, wherein parameters of a laser beam are selected to create carbon foam in that region, and wherein no substantial gas escape path to the surface of the precursor material is created by the laser beam.

[0066] Feature D: Amorphous non-graphene material adhered to substrate When the laser 11 irradiates the carbon film 14 mounted on the substrate 15, the laser carbonizes the surface of the carbon film adjacent the substrate 15 to form disordered amorphous non-graphene material 17 adjacent the substrate 15, which adheres to the substrate 15 and has internal, or sub-surface, or encapsulated carbon foam regions 16 which are themselves bonded to the disordered amorphous non-graphene material 17, resulting in the carbon foam regions 16 themselves not being directly attached to the substrate 15 but nevertheless being firmly positioned on the substrate 15 via the intermediate disordered amorphous non-graphene material 17. The carbon foam regions 16 are more firmly bonded compared to conventional laser-induced graphene and are less likely to delaminate even if the substrate is flexible, enabling, for example, biosensor applications where the substrate is often a thin, flexible structure.

[0067] It can be generalized as follows: 1. A method of producing a carbon foam material, the method comprising: irradiating an interior region of a carbon precursor material positioned on a substrate, where laser beam parameters are selected to create carbon foam in the region and to create disordered amorphous non-graphene material between the carbon foam region and the substrate, where the disordered amorphous non-graphene material adheres directly to or otherwise adheres to the substrate.

[0068] Group 2: Dual Laser Processing Feature E: Carbon foam created by laser ablation of sub-surface carbon foam regions Features A-D above cover the creation of carbon foam in sub-surface or encapsulated regions of a carbon precursor material. Because the carbon foam is not formed on an exposed surface, and many applications require the carbon foam to be exposed (e.g., functionalized for biomedical sensing applications or supercapacitors), additional steps can be performed to expose at least a portion of the sub-surface or encapsulated carbon foam.

[0069] It was previously determined that laser irradiation using an IR laser 11 forms a disordered amorphous non-graphene material 18 on the sub-surface or encapsulated carbon foam 16. Now, a laser, typically a far-IR CO2 laser 20, is used to ablate or otherwise process this disordered amorphous non-graphene material 18, thus exposing the underlying carbon foam 16. This second laser 20 is typically unfocused, unlike the first laser.

[0070] As mentioned previously, a standard 220mm x 180mm polyimide sheet was used (although other sizes of polyimide sheets can be accommodated), which size can be accommodated with standard laser scanning devices of the kind typically used for laser engraving, laser cutting, and laser plotting that trace paths defined in standard CAD programs, as well as standard flatbed screen printing devices and standard conveyor dryers. Other sizes of polyimide sheets can also be accommodated.

[0071] It has been discovered that this secondary laser irradiation step modifies the morphology and other properties of the underlying carbon foam in surprising and desirable ways, resulting in twisted or turbostratic multi-layered carbon foams not previously observed. Varying the parameters of the CO2 laser 20 modifies the carbon foam material properties, allowing carbon foams to be produced with properties optimized for various applications.

[0072] This newly exposed carbon foam includes one or more of the following properties: Easily controlled thickness or depth Greater flexibility compared to the extremely brittle graphene made using conventional laser processes. Strong adhesion to any underlying flexible substrate ·High porosity High conductivity Increased capacitance or charge storage Rapid absorption of organic solvents and aqueous solutions Higher hydrophilicity High EMI shielding Enhanced electrode quality -High wettability ·Stain resistance

[0073] It is noted that by varying the laser parameters of either or both of the lasers used in the dual laser process, it is possible to modify one or more of these properties, as well as the size and extent of the defects and the size (including relative sizes) of the Raman D and 2D peaks. In this manner, it is possible to produce carbon foams with properties tailored or particularly suitable for different applications. It was surprising that the operation of the second ablation laser could enable the creation of usable exposed carbon foam regions, particularly with properties that can be tuned by varying the parameters of the first and / or second lasers.

[0074] It can be generalized as follows: 1. A method of producing a carbon foam material, the method comprising: (a) a laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create carbon foam in the encapsulated or sub-surface region and create disordered amorphous non-graphene material above the carbon foam; and (b) laser ablation or treatment to remove the disordered amorphous non-graphene material and expose at least a portion of the carbon foam.

[0075] Feature F: Carbon foam created by laser ablation of sub-surface carbon foam regions Feature E above described forming carbon foam 16 in an encapsulated or sub-surface region of the carbon precursor by irradiating the region with a laser 11 (e.g., an IR laser). The irradiation expands (in the direction of the laser) the overlying carbon precursor material 14 into disordered amorphous non-graphene material 18. A second laser 20, e.g., a CO2 laser, then exposes or uncovers the overlying disordered amorphous non-graphene material 18. This second irradiation step not only ablates the overlying disordered amorphous non-graphene material 18, thus exposing the underlying carbon foam 16, but also imparts an unexpected and unusual surface morphology 21 to the underlying carbon foam with highly desirable properties; the resulting carbon foam may be a twisted or turbostratic multi-layered carbon foam.

[0076] However, because this foam may have properties not associated with graphene foam, such as a wide range of defects, appearance, wettability, and Raman spectra (see Feature R below), this Feature F explicitly describes this foam as a "non-graphene carbon foam." Thus, the term "non-graphene carbon foam" (unlike the term "carbon foam") explicitly excludes graphene foams, including twisted or turbostratic multilayer graphene foams, but is extended to cover other 3D carbon material foams.

[0077] It can be generalized as follows: 1. A method for producing a non-graphene carbon foam, comprising: (a) a laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create a carbon foam at the encapsulated or sub-surface region of the carbon precursor material and to create a disordered amorphous non-graphene material above the carbon foam; and then (b) laser ablation or treatment to remove the disordered amorphous non-graphene material and expose at least a portion of the underlying carbon foam and convert at least a portion of the underlying carbon foam to non-graphene carbon foam.

[0078] Feature G: Dual lasers with different bands In features E and F above, it was noted that two separate laser irradiation steps may be used. These are typically performed using two separate lasers, with the first step of creating sub-surface or encapsulated carbon foam typically being performed with a focused IR laser 11, and the second step involving laser irradiation at longer wavelengths using an unfocused CO2 laser 20, although other wavelengths (e.g., UV and visible) may also be used.

[0079] A second laser 20 ablates material 18 (e.g., a disordered amorphous non-graphene material) located between the carbon foam 16 and the surface, exposing the underlying carbon foam 16. The exposed carbon foam 16 may be modified (e.g., its surface morphology 21) by the second laser, i.e., the term "exposing" should be interpreted broadly to include not only exposing at least a portion of the pre-existing carbon foam, but also converting or modifying at least a portion of the pre-existing carbon foam into a 3D carbon material foam having properties different from those of the pre-existing graphene foam.

[0080] It can be generalized as follows: 1. A method of making a carbon foam material, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material above the carbon foam to expose at least a portion of the carbon foam.

[0081] Feature H: Electrical contacts located in carbon foam created by laser ablation of sub-surface carbon foam regions Previously, we have identified a method for making carbon foam, which can be twisted or turbostratic multi-layer carbon foam. This material has excellent electrical properties (conductivity, capacitance, etc.), so that one or more electrical contacts (including electrical items such as flexible electronics, microprocessors, antennas, IoT devices, electrical interfaces, etc.) can be attached or placed on the carbon foam. In the case of printed traces (e.g., screen printed silver traces), these are screen printed onto a polyimide film (or other suitable substrate) and printed onto and into the existing 3D carbon material foam, such that the traces make good electrical contact with the foam and any structures formed on the foam, such as functionalized layers (see feature L below, which describes how carbon foam is functionalized to form a biosensor with an analyte-specific receptor layer, for example).

[0082] It can be generalized as follows: 1. A method of making a carbon foam material, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) removing or ablating material overlying the carbon foam using a laser beam operating in a second band to expose at least a portion of the carbon foam; (c) attaching, printing or placing one or more electrical contacts into the carbon foam.

[0083] Feature I: Printing of electrical contacts on polyimide film and then creating exposed carbon foam In Feature H, we saw that once the dual laser process is complete, electrical contacts or circuitry are added that contact the existing carbon foam. For example, simple silver electrical contacts can be screen printed onto the carbon foam. In this Feature I, we describe starting the process by first screen printing electrical contacts onto a polyimide film, then finishing the process by using a second laser ablation step of the dual laser process to create exposed carbon foam. This has several advantages since the screen printing process can disturb or destroy the carbon foam. This is a process called "PPC," an abbreviation for Post Printing Conversion, where a screen printing step is performed prior to the dual laser process to create the carbon foam. In Feature L5, we now describe a biosensor fabricated using the PPC process.

[0084] Thus, for screen printed tracks (e.g., screen printed silver tracks), these are screen printed onto a polyimide film (or other suitable substrate) in such a way that carbon foam is then formed around one end of the printed tracks, providing a large surface and therefore a contact area with very good electrical connectivity. As with the alternative process described in Feature H above, the printed tracks make good electrical contact with any structures formed on the foam, such as functionalized layers (see, e.g., Feature L below, which describes how carbon foam is functionalized to form a biosensor with an analyte-specific receptor layer).

[0085] An alternative sequence involves using a first laser beam to create a sub-surface carbon foam, then screen printing the electrical contacts, and then using a second laser beam to create the carbon foam in a way that makes good electrical contact with the electrical contacts.

[0086] It can be generalized as follows: 1. A method of making a carbon foam material, comprising: (a) screen printing electrical contacts onto or within a carbon precursor material; (b) using a laser beam operating in a first band to irradiate an encapsulated or sub-surface region of the carbon precursor material below the surface of the material to create carbon foam in the encapsulated or sub-surface region, wherein steps (a) and (b) can be performed in the order of (a) followed by (b), or (b) followed by (a); (c) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam to which the electrical contacts are connected.

[0087] Feature J: Toll Raceways Made with Carbon Foam It has been previously determined that the thickness of the sub-surface carbon foam region or encapsulated carbon foam region can far exceed the thickness of conventional graphene foam, which is limited to the surface layer. The laser focus of the first laser beam can be moved progressively down through the carbon precursor material to create a deep or thick layer of sub-surface carbon foam or encapsulated carbon foam. A second laser irradiation step is then deployed to ablate the material located between the carbon foam and the surface of the carbon precursor material, resulting in an exposed region of carbon foam. The thickness or depth of this newly exposed carbon foam region can be at least 50 μm, with carbon foams as thick as 300 μm being produced. The increased thickness is beneficial as it can result in better electrical conductivity, greater capacitance, and greater mechanical integrity.

[0088] It can be generalized as follows: 1. A method of making a carbon foam material, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; The method wherein the carbon foam is at least 50 μm thick or deep.

[0089] Feature K: Application of primary and secondary lasers in different manufacturing facilities The specific properties or structure of the carbon foam resulting from the second laser may be considered confidential information since they define the characteristics of the final product. It is likely desirable for the first laser beam process to be performed by the carbon foam supplier at their manufacturing facility, and then the supplier will supply the carbon foam to a customer who will then perform the final step at their own manufacturing facility using the second laser beam. As mentioned above, by varying the parameters of the first laser and even the second laser, it is possible to modify the properties of the carbon foam material and produce carbon foams with properties optimized for different applications. Typical parameters that may be modified or adjusted in this way may include intensity, wavelength, pulse frequency, pulse duration, pulse profile, scan speed, focal length, heat generated in the sub-surface area or encapsulated area.

[0090] By splitting the manufacturing process in this way, the supplier is insulated from knowing the specific manufacturing process used by the customer as part of the second laser ablation process (e.g., how to vary the parameters of the second laser beam to give the exposed carbon foam the properties they need), and the customer can keep the details of how they produce the finished product strictly confidential.

[0091] The manufacturing process is therefore a three-step process involving: (a) a first laser beam irradiating a sub-surface region of a carbon precursor material at a manufacturing site to produce an unfinished carbon foam product; (b) the unfinished carbon foam product is transported to a customer-controlled manufacturing site; and (c) laser ablation or processing occurs at the customer-controlled manufacturing site.

[0092] Additionally, this approach allows for large-scale production (see, e.g., feature P) of carbon foam produced by only the first laser process, reducing the cost of this material, which can be used for many different applications and customers. More specialized products produced using the second laser beam are likely produced in much smaller quantities than carbon foam produced by only the first laser process. Thus, this approach allows for more efficient, lower-cost production of the base material, i.e., carbon foam produced by only the first laser process.

[0093] It can be generalized as follows: 1. A method of manufacturing a device, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; The process, wherein step (a) is performed in one manufacturing facility and step (b) is performed in a different facility.

[0094] Of features A-K, the following optional features are of particular relevance: It should be noted that any one or more of the following optional features may each be combined with any one or more other compatible optional features, and with any one or more of features A-K.

[0095] It covers the following areas: Manufacturing process First laser beam parameters and control scheme Subsurface or encapsulated area attributes Carbon precursor materials Substrate supporting the carbon precursor material Carbonization at the surface where the laser beam is incident Ablative laser beam or second laser beam Carbon foam

[0096] Please note that any one or more of the following optional features may each be combined with any one or more other compatible optional features, and with any one or more of the other "features" listed herein (e.g., Features A-R).

[0097] The laser-based manufacturing process described above has many advantages over conventional CVD processes, which can be listed as the following optional features: - Room temperature process. Atmospheric pressure process. · It can be performed on plastic substrates (compatible with any manufacturing process, not just silicon chip manufacturing). -Can be done without a catalyst. 1cm of carbon foam approximately 50μm thick 2 takes about 2 minutes or less to produce on a plastic substrate. Allows 3D carbon foam to be fabricated on flexible substrates No graphene or graphene oxide precursors are required. The carbon foam material is produced only in the encapsulated sub-surface region of the carbon precursor material, and not on any surface of the carbon precursor material. · It uses a combination of industry standard, low cost and scalable (i) screen printing technology and (ii) computer controlled laser scanning technology. Can be adapted for high speed, high volume reel-to-reel or reel-to-sheet production.

[0098] The parameters and control scheme of the first laser beam are important to the production of carbon foam, and we define here the relevant optional features: Parameters of the laser beam irradiating the sub-surface region or encapsulated region include one or more of the following: intensity, wavelength, pulse frequency, pulse duration, pulse profile, scan speed, focal length, and heat generated at the sub-surface region or encapsulated region. Varying the laser parameters allows the carbon foam material properties to be modified, allowing carbon foams with optimized properties for different applications to be produced. Varying the laser parameters alters one or more of the following carbon foam material properties or parameters: defect size, defect distribution, defect extent, defect type, Raman D and 2D peaks, relative size of Raman D and 2D peaks, thickness or depth, flexibility, adhesion, porosity, electrical conductivity, capacitance, absorption of organic solvents and aqueous solutions, hydrophilicity, EMI shielding, electrode quality, wettability, contact angle, anti-fouling. The laser beam creates temperatures of greater than 500°C in the sub-surface or encapsulated area, forming a carbon foam. The laser beam produces temperatures in excess of about 500°C in the sub-surface or encapsulated area, forming a carbon foam. The laser pulse duration is about 1 ns to 10 μs, and the laser power is about 5×10 7 ℃ / sec~2×10 12 The heating rate in °C / sec is given. Laser power is in the typical operating range of 8-20 watts, with 12W being optimal. The focal length of the laser is in the typical working range of 50mm to 400mm. The laser pulse frequency is about 50kHz to 500kHz. The laser pulse frequency is about 1kHz to 2MHz. The laser wavelength is approximately 0.7μm to 2.5μm. The laser scans at approximately 9cm / sec to 40cm / sec. Laser beam parameters include focus parameters. Laser beam parameters include diffraction parameters. Laser beam parameters include interference pattern parameters. The focal point of the laser beam travels through the depth of the carbon precursor material to produce carbon foam in sub-surface or encapsulated regions of the carbon precursor through which the focal point passes. The focal point of the laser beam travels at least about 50 μm through the depth of the carbon precursor material to produce carbon foam in a sub-surface region or encapsulated region of the carbon precursor at least 50 μm thick. The focal point of the laser beam travels at least about 100 μm through the depth of the carbon precursor material to produce carbon foam in a sub-surface region or encapsulated region of the carbon precursor at least 100 μm thick. The laser beam is scanned (e.g., rastered) or moved laterally across the carbon precursor material to form the desired pattern. The laser beam is scanned, or moved laterally, across the carbon precursor material to form the desired pattern, including non-overlapping areas or lines. The laser beam is repeatedly scanned (e.g., rastered) or moved laterally across the carbon precursor material with focal points or intensity maxima located at multiple different depths within the carbon precursor material until a carbon foam of the required pattern and depth is created. The laser beam may be scanned at a scan speed of 1.7 mm / s to 3550 m / s, or more typically 35 mm / s to 350 mm / s, such that the scan has a pulses per inch (PPI) of 100 to 10,000 (relevant to the production of individual polyimide sheets of approximate size 220 mm x 180 mm). The laser beam has a wavelength that is substantially free of absorbance by the carbon precursor material. The laser beam has a wavelength that has very low absorbance by the carbon precursor material, such as less than 50, or less than 20, or less than 10 radiation absorbance per cm (base 10). The laser beam is an IR laser. The laser beam is an IR laser with a wavelength of approximately 0.7 μm to 2.5 μm. The laser beam is an IR laser with a wavelength of approximately 0.75μm to 1.40μm.

[0099] The attributes of the sub-surface region or encapsulated region from which the carbon foam is created can be defined by the following optional features: Unlike conventional graphene foams, the sub-surface or encapsulated regions can be greater than about 50 μm thick. A desired depth of the sub-surface region or encapsulated region in the carbon precursor material is achieved by moving the focus of the first laser beam through its depth. The subsurface region or encapsulated region may be at various depths below the surface of the carbon precursor material facing the incident laser, and exactly at what depth the subsurface region or encapsulated region is a function of various factors such as the laser intensity, the choice of carbon precursor material used, etc. For example, the subsurface region or encapsulated region may be at least about 10 μm, 20 μm, 30 μm, 40 μm, 50 μm or more below the surface of the carbon precursor material. The sub-surface region or encapsulated region may have a thickness of about 10 μm to 200 μm. The sub-surface region or encapsulated region is a distance below the surface of the carbon precursor material that is a function of various factors such as the laser intensity, other laser parameters, the choice of carbon precursor material used, etc. For example, the top of the sub-surface region or encapsulated region can be below the surface by at least 1%, 10%, 20%, 30%, 40% of the total thickness of the carbon precursor material. The sub-surface region or encapsulated region is the volume of space centered at the midpoint of the smallest cross section of the first laser beam, the volume being within 500 or 100 microns, or within 1 micron of this midpoint.

[0100] The carbon precursor material may be defined by the following optional characteristics: The carbon precursor material is essentially made of a thermosetting material. The carbon precursor material is made of substantially non-thermoplastic materials. The carbon precursor material is a thermoset film. The thermosetting film is a polyimide film. The carbon precursor is a polyimide film. The carbon precursor is a polyimide film, and the wavelength of the first laser is in the range of 0.7 μm to 2.5 μm. The carbon precursor is at least 50% by weight carbon, or at least 75% by weight carbon, or at least 90% by weight carbon. The carbon precursor is a film or sheet. Carbon precursor materials are flexible. The carbon precursor material is a printed layer, such as a screen printed layer. The carbon precursor material has a thickness of more than 5 μm, or between 5 μm and 120 μm, or greater than 120 μm. The carbon precursor material is substantially planar or flat and oriented perpendicular to the first laser beam. The carbon precursor material is homogeneous. The carbon precursor material is heterogeneous and contains several different materials. The carbon precursor is supported on a substrate that is not made of the carbon precursor. The absorption coefficient of the carbon precursor material at the wavelength of the first laser beam is low. The absorption coefficient of the carbon precursor material for the first laser beam is 50 cm -1 Less than or equal to 20cm -1 Less than or equal to 10cm -1 is less than. The absorption coefficient of the carbon precursor material for the second laser beam or the ablative laser beam (see Group 3 characteristics below) is less than or equal to 300 cm -1 is less than. The absorption coefficient of the carbon precursor material for the second laser beam or the ablation laser beam is 300±50 cm -1 It is. The carbon precursor material has a thermal conductivity of less than 1.0 W / mK (using a method according to ASTM D5470). The carbon precursor material has a thermal conductivity of less than 0.5 W / mK (using a method according to ASTM D5470). The carbon precursor material is mounted on a substrate that is substantially optically transparent at one or more wavelengths of the first and / or second laser beams. Carbon Precursor Material The carbon source may comprise or be formed from one or more polymers. Carbon precursor materials include one or more of the following materials: polyimides (e.g., poly(4,4'-oxydiphenylene-pyromellitimide), also known as polyimide), polyetherimide (PEI), poly(methyl methacrylate) (PMMA) (e.g., spray-coated PMMA), polyurethane (PU), polyester, vinyl polymers, carbonized polymers, photoresist polymers, alkyds, and urea-formaldehyde. The carbon precursor includes one or more of the following materials: a poly(amic acid) (e.g., an aryl-containing poly(amic acid)) (e.g., poly(pyromellitic dianhydride-co-4,4'-oxydianiline), an amine acid - also known as a polyamic acid), a dianhydride (e.g., an aryl dianhydride) (e.g., pyromellitic dianhydride), a derivative of the poly(amic acid), or a derivative of the dianhydride (e.g., a derivative of pyromellitic dianhydride). The carbon precursor comprises one or more of the following materials: aromatic materials (e.g., aromatic polymers), heteroaromatic materials (e.g., heteroaromatic polymers), polymers containing aromatic moieties, cyclic materials (e.g., polymers containing cyclic moieties), heterocyclic materials (e.g., polymers containing heterocyclic moieties), heteroaromatic materials (e.g., polymers containing heteroaromatic moieties). The carbon precursor includes a material that contains one or more of an aromatic bond, or a heteroaromatic bond, or a hetero bond (eg, an imide bond).

[0101] The substrate can be considered as the material presenting the surface on which the carbon precursor is located, the specific material, thickness and properties of the substrate are determined by the application, for example, for some sensors the substrate can be a thin flexible plastic film, for other applications the substrate can be a rigid polyimide substrate on which electronic circuitry can be attached. The IR laser can directly irradiate the carbon source, or alternatively the radiation from the IR laser may first pass through the substrate before reaching the carbon source, in which case there are two alternative scenarios, first the substrate is substantially transparent to IR radiation and the mechanism of carbon foam formation is as described above. However, in the second scenario the substrate is substantially opaque to IR radiation and then rapid heat transfer from the substrate to the carbon precursor material first produces a disordered amorphous non-graphene layer at the interface layer with the substrate, and then the carbon foam forms in the interior sub-surface or encapsulated regions of the carbon precursor material.

[0102] The substrate upon which the carbon precursor material may be positioned and supported may be defined by the following optional features: The substrate is a plastic body, a film, or a foil. The substrate is flexible. The substrate is a polyimide circuit board. The substrate has very low absorbance of the first laser beam. The substrate is substantially optically transparent at the one or more wavelengths of the first laser beam. The substrate has a high absorbance of the first laser beam, absorbing more than 60% of the first laser beam. The substrate has a high absorbance of the first laser beam, absorbing more than 60% of the first laser beam, and has a thermal conductivity of at least 10 W / mK. The surface of the carbon precursor material is transformed by the laser beam into a disordered amorphous non-graphene material that sticks or bonds to the substrate, thus indirectly attaching the 3D carbon material foam to the substrate. The substrate is formed from one or more of the following: silicon (Si), silicon dioxide (SiO2), gallium nitride (GaN), gallium arsenide (GaAs), zinc oxide (ZnO). The substrate is a silicon wafer. The substrate is a silicon dioxide wafer. The substrate is a wafer that includes both silicon and silicon dioxide. The substrate is a carbon source. The substrate is not a carbon source, e.g. a metal, a dielectric material, a screen printed dielectric material. The carbon precursor is positioned "above" the substrate (e.g., the carbon precursor is positioned closer to the laser source than the substrate). The carbon precursor is positioned "below" the substrate (e.g., the carbon precursor is positioned further from the laser source than the substrate).

[0103] Carbonization of the surface on which the laser beam is incident can be defined by the following optional characteristics: The surface of a carbon precursor material is transformed by a first laser beam into a disordered amorphous non-graphene material. The disordered amorphous non-graphene material occupies a thickness below the surface of the adjacent carbon precursor material that is about 1%, or less than about 1%, or less than about 5%, or less than about 10% of the total thickness of the carbon precursor material. The disordered amorphous non-graphene material extends a distance that is at least 10 μm below a surface of the carbon precursor material. The disordered amorphous non-graphene material extends from the outer surface into the body of the carbon precursor material to a depth of 10 μm or less, or to a depth of 20 μm or less, or to a depth of 30 μm or less, or to a depth of 40 μm or less, or to a depth of 50 μm or less, or to a depth of 100 μm or less.

[0104] The ablative laser beam or the second laser beam may be defined by the following optional features: The laser beam parameters include one or more of the following: intensity, wavelength, pulse duration, pulse profile, scanning speed, heat generated in the sub-surface region or encapsulated region. Varying the laser parameters allows the carbon foam material properties to be modified, allowing carbon foams with optimized properties for different applications to be produced. Varying the laser parameters alters one or more of the following carbon foam material properties or parameters: type of carbon nanostructures present (e.g. carbon nano-onions, etc.), size of defects, distribution of defects, extent of defects, type of defects, Raman D and 2D peaks, relative size of Raman D and 2D peaks, thickness or depth, flexibility, adhesion, porosity, electrical conductivity, capacitance, absorption of organic solvents and aqueous solutions, hydrophilicity, EMI shielding, electrode quality, wettability, contact angle, anti-fouling. The laser beam that ablates the amorphous non-graphene material formed above the encapsulated or sub-surface regions in the carbon precursor (the “second laser beam”) is a CO2 laser. The second laser beam modifies the carbon foam as part of the process to expose the carbon foam. The second laser beam modifies the morphology of the carbon foam as part of the process to expose the carbon foam. The second laser beam is automatically controlled to be scanned (e.g., raster scanned) across the same area and / or overlapping and / or non-overlapping areas. The laser beam wavelength for ablating amorphous non-graphene material is 8μm~15μm. The second laser beam is a far IR laser, or a UV laser, or a visible laser. The second laser beam has a pulse frequency of 50 kHz to 500 kHz and a scanning speed of 9 cm / sec to 40 cm / sec. The absorption coefficient of the carbon precursor material is 100 cm for the second laser beam. -1 or 200 cm to the second laser beam -1 It's super. The absorption coefficient of the carbon precursor material is 300±50cm for the second laser beam. -1 It is. Laser power is in the typical operating range of 8-20 watts, with 12W being optimal. The focal length of the laser is in the typical working range of 50mm to 400mm. The second laser beam is scanned in a pattern that includes non-overlapping areas or lines. The second laser beam is scanned in a pattern that matches the scan pattern of the first laser beam. The second laser beam is unfocused. The manufacturing process is a three-step process involving: (a) a first laser beam irradiating a sub-surface region of a carbon precursor material at a manufacturing site to produce an unfinished carbon foam product; (b) the unfinished carbon foam product is transported to a customer-controlled manufacturing site; and (c) laser ablation or processing occurs at the customer-controlled manufacturing site.

[0105] Carbon foam may be defined by the following optional characteristics: The carbon foam is at least 50μm thick. Carbon foam is 50μm to 300μm thick. The carbon foam is or includes a twisted or turbostratic multilayer foam. The carbon foam is or includes a carbon foam having a spatial distribution of defects that results in high electrochemical reactivity. The carbon foam is or includes a carbon foam having basal plane defects at vacancy sites that result in high electrochemical reactivity. Carbon foam has a carbon:oxygen ratio of 25:1 to 50:1. Carbon foam has a fast electron transfer constant. Carbon foam has one or more of the following properties: Easily controlled thickness or depth Greater flexibility compared to the extremely brittle graphene made using conventional laser processes. ·Strong adhesion to underlying flexible substrate ·High porosity High conductivity Increased capacitance or charge storage Rapid absorption of organic solvents and aqueous solutions Higher hydrophilicity High EMI shielding Enhanced electrode quality Contact angle of approximately 20° or less Carbon foam properties are selected by choosing specific laser parameters that result in carbon foam having one or more of the following desired properties or parameters: defect size, defect distribution, defect extent, defect type, Raman D and 2D peaks, relative size of Raman D and 2D peaks, thickness or depth, flexibility, adhesion, porosity, electrical conductivity, capacitance, absorption of organic solvents and aqueous solutions, hydrophilicity, EMI shielding, electrode quality, wettability, contact angle, anti-fouling.

[0106] Group 3: Products Feature L1: Biosensor Carbon foams made by the dual laser method described above have a wide range of applications across many different types of sensors. For simplicity, we use the phrase "carbon foam" in this feature L to refer to any carbon foam or 3D carbon material foam made by the methods described herein. Appendix 1 contains details on this field and describes in more detail a biosensor that includes a carbon foam that has been functionalized by adding a receptor that is specific for a target or analyte, and a linker that allows the receptor to be indirectly attached to the carbon foam (some receptors cannot be directly attached to the carbon foam due to their low stability when in contact with the surface, and instead a linker must be used as an intermediate between the carbon foam and the receptor. During fabrication, the linker is first added to the carbon foam, and then the receptor is added to the linker.)

[0107] For biosensor applications, functionalized carbon foams have the following advantages compared to conventional graphene foams: higher electron transfer rates, higher detection sensitivity, larger electrochemically active areas, higher reproducibility, lower cost, and enhanced wettability with contact angles below about 20°.

[0108] At a high level, functionalized carbon foams are useful in sensors due to their ability to produce a detectable change in state, and their high sensitivity is a function of their large surface area. Functionalized carbon foams can be used to detect specific chemicals, specific gases, mechanical stress, and temperature, as well as other variables. Each category will be briefly examined.

[0109] First, chemical sensors: Chemical detection systems rely on detecting the electrical response of carbon foam in the presence of target chemicals and can use many different detection principles, such as changes in capacitance, electrical resistance, voltammetry, redox potential, and charge transfer resistance.

[0110] For example, when a specific analyte or target binds to the carbon foam, the binding modifies the surface of the carbon foam, and the binding can be detected. A biomolecule such as a specific antibody or an aptamer (aptamers are short, single-stranded DNA or RNA molecules that can selectively bind to specific targets, including proteins, peptides, carbohydrates, small molecules, toxins, and living cells) is added to the carbon foam. When the target is present and binds to the aptamer, the morphology of the aptamer is altered (e.g., the surface area is reduced), and the volume of the combined carbon foam and aptamer system is measurably reduced.

[0111] Using this principle, highly sensitive and selective sensors can be built, and since the measurable variable (such as capacitance) is quantitatively reduced, it is possible to build a LOC (Lab-on-a-Chip) that includes not only the carbon foam and aptamer biosensor, but also a power source on the LOC such as a supercapacitor or other energy store using the carbon foam as an electrode, and circuitry for measuring the variable, calculating the biosensor output, and displaying the output (e.g., presence or absence of target, or concentration of target) on a screen on the LOC; feature O3 (Gii-Thru for Gii-Sens:HISLOC) further explains this.

[0112] Carbon foam sensors can also measure the redox potential of a target; for example, if the oxidation of a target chemical is catalyzed by a particular catalyst added to the carbon foam, a current peak can be detected, and since the current is typically a function of the concentration of the target chemical, a quantitative measurement of the target concentration is possible.

[0113] Other techniques applied to conventional graphene sensors, such as thermal conductivity measurements to detect specific chemicals, electrical resistance measurements to infer temperature, physical morphing or transformation in the presence of specific chemicals, piezoresistive deformation to detect motion, etc., can all be applied to carbon foam sensors made by the dual laser method described above.

[0114] An important application that takes advantage of the very large electrochemically active area and fast electron transfer kinetics of the carbon foam produced by the dual laser method is an electroanalytical sensing electrode (implementation called "Gii-Sens") optimized for biosensing.

[0115] Electroanalytical sensing electrodes can be used, for example, in point-of-care diagnostic devices, where the sensing electrodes have very high sensitivity, reliability, purity, wettability, and conductivity.

[0116] 20A is a perspective view of a biosensor called Gii-Sens. The assembly consists of a polyimide substrate 201, a working electrode 202 made of Gii carbon foam, a counter electrode 203 made of Gii carbon foam, a reference electrode 204 made of screen printed silver-silver chloride, three screen printed silver interconnect tracks 205, and a screen printed dielectric layer 206.

[0117] 20B-20D show the four main fabrication steps. FIG. 20B shows that a dual laser process uses a polyimide substrate 201 as a precursor to fabricate a Gii carbon foam working electrode 202 (area 18.94 mm 2 ) and the counter electrode 203 (area is 20.84 mm 2 1 shows step 1 for preparing the compound (

[0118] FIG. 20C shows a silver-silver chloride reference electrode 204 (area 8.99 mm 2 2 shows step 2 in which a polyimide film (202) is screen printed onto a polyimide substrate 201.

[0119] Figure 20D shows step 3 where silver interconnect tracks 205 are screen printed onto the polyimide substrate 201; these overlap the carbon foam electrodes at the electrical contact areas 207. The silver track area is 1 x 18.85 mm 2 and in the case of three, it is 3 x 56.55 mm. 2 The overlap area with the underlying carbon foam electrode is 1 × 2.21 mm 2 and in the case of three, it is 3 x 6.63 mm. 2 It is.

[0120] 20E shows step 4 where a dielectric layer 206 is screen printed onto the carbon foam electrodes 202, 203, 204 and silver interconnect traces 205. The active areas of the electrodes are as follows: Working electrode 202: 12.64 mm 2 , Counter electrode 203: 14.18 mm 2 , Reference electrode 204:2.59mm 2 The exposed area of ​​the silver interconnect 205 is 1×7.15 mm 2 and 2 x 21.45 mm2 It is.

[0121] 20F shows a single polyimide sheet on which an array of 100 carbon foam working and counter electrodes have been fabricated using the dual laser process of step 1 described above. The sheet is a standard type polyimide sheet, 220 mm by 180 mm, to allow handling with standard screen printing and laser scanning equipment, which can be made A5 size or other suitable size.

[0122] Figures 20G and 20H show the final form of the sheet after completion of step 4. 100 individual units can be cut and assembled into 100 completed Gii-Sens biosensors.

[0123] One specific use case of the Gii-Sens sensing electrodes is a reversible polymer displacement sensor mechanism for electrochemical glucose monitoring. A graphene sensor for this use case has been proposed, see "Polymer indicator displacement assay: electrochemical glucose monitoring based on boronic acid receptors and graphene foam competitively binding with poly-nordihydroguaiaretic acid" by Wikeley et al. DOI:10.1039 / d1an01991k. This paper describes the adsorption of a pyrene-derivatized boronic acid chemical receptor for glucose onto a graphene foam electrode. Spontaneous oxidative polymerization of nordihydroguaiaretic acid (NHG) onto the graphene foam electrode results in a redox-active film (polyNHG) covalently bound to the boronic acid receptor. Oxidation of polyNHG liberates the boronic acid receptor from the solution phase to interact with glucose, which is detected due to competitive binding when reduced polyNHG rebinds to the boronic acid functional group. The sensor shows the expected boronic acid selectivity for fructose-glucose. The ratio of the charges under the voltammetric peaks for unbound and bound polyNHG is used for glucose sensing with a nearly linear analytical range of 1 to 50 mM glucose in pH 7 buffered aqueous solution.

[0124] The implementation of the Gii-Sens sensing electrodes has many advantages compared to current sensing electrodes such as graphene sensors: Lower detection limits using amplification-free, enzyme-free, label-free electrochemical biosensing Enhanced reproducibility Optimize the useful dynamic range Minimize background noise Reduce protocol time and operations Scalable for low-cost manufacturing High sensitivity and selectivity -Gives quantitative digital results Capable of being printed in specific patterns, e.g., interdigitated patterns that allow for miniaturized integrated devices Existing biorecognition and testing formats (e.g., ELISA, PCR, RT-PCR) can be converted to electrochemical microfluidic POC without compromising performance quality Impedance-based measurements can be performed with very high sensitivity, reliability, and very low background signal interference. Replace costly large-scale laboratory tests with less sensitive lateral flow tests Can be implemented in microfluidic assays (single-target or multi-target) and lab-on-a-chip (LOC) devices Can be used for any sensor application where the user aims to immobilize a (bio)molecule of interest (e.g., carboxyl / n-hydroxysuccinimide moieties can be added to the sensor surface to provide a platform for subsequent immobilization conjugation chemistry) Can be used across a wide range of diagnostics: point-of-care human and animal health, food safety, field environmental health and safety, agricultural health and safety, all with enhanced biosensing sensitivity, selectivity and reproducibility due to its pure and high specific surface area. Enhanced wettability (e.g., contact angles less than about 20°) Enhanced anti-fouling properties

[0125] It can be generalized as follows: A method of manufacturing a biosensor comprising a sensing electrode comprising a carbon foam made at least in part by the method defined in any of Features A-K above.

[0126] L2: Scalable, low-cost fabrication of carbon foam biosensors using screen printing technology Above, we have seen how screen printing is widely used in the manufacturing process. It is a well-known, scalable, predictable, and low-cost technology. The detailed manufacturing process of Gii-Sens carbon foam biosensor is shown in Figure 21.

[0127] It can be generalized as follows: A method of manufacturing a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each of which comprises, at least in part, a carbon foam made by a method defined in any of Features A-K above, the method comprising: screen printing an electrical connection trace onto each electrode; and at least partially covering the electrodes and the connection traces with a screen printed dielectric.

[0128] Optional features include: The method as defined above, wherein in step 1, a dual laser process fabricates carbon foam working and counter electrodes using a PI substrate as a precursor. A method as defined above, wherein in step 2, a reference electrode, such as a silver-silver chloride electrode, is screen-printed onto the PI substrate. A method as defined above, wherein in step 3, connecting traces, such as silver traces, are screen printed onto the PI substrate so as to overlap the carbon foam electrodes. Note that the order of steps 2 and 3 can be reversed. The method as defined above, wherein in step 4, a dielectric layer is screen printed over the carbon foam electrodes and at least a portion of the silver interconnect traces.

[0129] Other aspects are as follows: A biosensor including sensor electrodes, such as a working electrode and a counter electrode, each at least partially comprising carbon foam made by the method defined in any of Features A-K above, and each electrically connected to a screen printed trace and at least partially covered by a screen printed dielectric.

[0130] A point-of-care diagnostic device comprising a biosensor as defined above.

[0131] L3: Adding functional groups to biosensors in a different manufacturing facility In the case of Gii-Sens biosensors, the biosensors are manufactured in one facility, but the customer adds functional groups to which biomolecules can be attached in a different facility, typically the customer's own facility, thus speeding up the development and testing of these functional groups and also protecting trade secrets and know-how in these functional groups as well as the final design of the biosensor.

[0132] It can be generalized as follows: A method of manufacturing, at one manufacturing facility, biosensors including sensor electrodes, such as a working electrode and a counter electrode, each comprising carbon foam made at least in part by a method defined in any of Features A-K above, the method including the further step of adding a functionalizing group to the working electrode at a different manufacturing facility.

[0133] L4: Addition of functional groups to the biosensor as part of the biosensor generation process For the Gii-Sens+ biosensor, the fabrication process involves adding functional groups. Figure 22 shows the detailed fabrication process of Gii-Sens+.

[0134] It can be generalized as follows: A method of manufacturing a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each comprising carbon foam made at least in part by a method defined in any of Features A-K above, at a single manufacturing facility, the method including the further step of adding a functionalizing group to the working electrode at the manufacturing facility.

[0135] L5: Biosensor manufacturing using PPC: Post-print conversion The PPC variant of the Gii-Sens manufacturing process is shown in Figure 23. PPC is the abbreviation for Post Printing Conversion, in which a screen printing step is performed before the dual laser process to create the carbon foam. The specific steps are as follows: 1. Screen print a carbon layer onto a substrate (e.g., polyimide) 2. Screen print the Ag / AgCl reference electrode 3. Screen print the Ag electrical connection wiring paths 4. Screen print the dielectric 4. Creating carbon foam on substrate using dual laser process

[0136] All screen printing steps (1-3) can be done using a reel-to-reel or reel-to-sheet process, and then a dual laser process can be used to create the carbon foam and then the materials can be kept flat and stacked.

[0137] Also, only the initial laser process (sub-surface foam creation) can be performed at the factory, and then the sheets are shipped to a customer who performs the second step of the dual laser process (laser ablation), and the customer can add the functionalization groups at their own manufacturing facility, different from the facility where the initial laser process step (or both laser process steps) of the dual laser process is performed. Alternatively, the functionalization can be performed at the facility where the dual laser process is performed.

[0138] Screen printing before making the carbon foam has the advantage that it is not dried so that it is not hydrophobic. The carbon layer acts as a bridge between the carbon foam (e.g., carbon foam and non-graphene disordered amorphous foam) and the silver connections formed in the polyimide.

[0139] It can be generalized as follows: A method of manufacturing a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each comprising carbon made at least in part by a method defined in any of Features A-K above, the method comprising: (a) screen printing a carbon layer onto a substrate; (b) screen printing an electrical connection trace and a reference electrode; (c) screen printing a dielectric layer onto the carbon and the electrical connection traces and the reference electrode; and (d) fabricating a carbon foam sensor electrode using the process defined in any of Features A-K above.

[0140] Feature M1: Energy storage device: Supercapacitor Carbon foams produced using any of the features AK have very large electrochemically active areas and fast electron transfer rates, making them ideal materials for electrodes in capacitors or supercapacitors or pseudocapacitors.

[0141] An important application is in supercapacitors (implementation is called "Gii-Cap") or other energy storage devices (e.g., lithium ion batteries). For supercapacitor and other electronic device applications, carbon foams have the following advantages over conventional graphene foams: larger surface area, more porous structure, higher quality, lower sheet resistance, higher wettability.

[0142] Carbon foam can be treated with metal oxides or other pseudocapacitive materials for pseudocapacitance (e.g., to create metal oxide layers or films) in a variant called Gii-Cap+, where the metal oxide films have very large surface areas and fast surface Faradic mechanisms.

[0143] It should be noted that when the term Gii-Cap is used, it includes the Gii-Cap+ variant unless the context makes it clear that it specifically excludes the Gii-Cap+ variant. It should also be noted that the term "supercapacitor" is used to include both (i) electric double layer (EDLC) capacitors, in which charge is stored electrostatically without interaction between the electrodes and electrolyte ions, and further (ii) pseudocapacitors, in which there is electronic charge transfer between the electrodes and electrolyte, and any energy storage device that uses a combination of electric double layer capacitance and pseudocapacitance. Finally, it should be noted that the term "supercapacitor" should be interpreted broadly to cover any electrochemical capacitor, including EDLC supercapacitors, pseudocapacitors, and hybrids thereof. Although the Gii-Cap+ variant is primarily a pseudocapacitor, we nevertheless refer to it as a "supercapacitor."

[0144] The carbon foam electrodes of the Gii-Cap supercapacitor enhance both the electrostatic double layer capacitance and the electrochemical pseudocapacitance compared to conventional supercapacitors. Appendix 2 provides further details of the supercapacitor and describes an implementation in which a hydrogel electrolyte (e.g., high molarity salt) encapsulates the interdigitated carbon foam electrodes in the active area to produce an enhanced operating voltage window.

[0145] The implementation of the EDLC supercapacitor Gii-Cap and pseudocapacitor Gii-Cap+ has many advantages over conventional rechargeable batteries: ·Fast charging High output Recyclable Non-explosive Flexible form and shape Solid gel electrolytes or polymer electrolytes (e.g. ionic gels or hydrogels) that are solid at room temperature and have a high transition temperature (e.g. 90°C) well above normal operating temperatures can be used, thus minimizing the risk of electrolyte leakage.

[0146] It can be used across a very wide range of devices and power storage requirements, including Lab-on-a-Chip (LOC), IoT devices, e-mobility, UAV and EV applications.

[0147] It can be generalized as follows: An energy storage device, such as a supercapacitor, wherein an energy storage electrode comprises, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0148] Feature M2: Screen-printed layers of carbon foam supercapacitors FIG. 24 is an exploded perspective view of a Gii Cap supercapacitor. It is composed of an array of carbon foam electrodes 241 connected to a pair of screen printed silver connectors 242 made using the dual laser process described above. A dielectric layer 243 is screen printed onto the carbon foam electrodes 241 and the screen printed silver connectors 242. The carbon foam electrodes 241 are formed on a polyimide base layer 244. A pair of copper connection tabs 245 are connected to the pair of screen printed silver connectors 242. An electrolyte layer 246 covers the carbon foam electrodes 241 (e.g., an ionic gel electrolyte such as a polymer hydrogel electrolyte that is a gel or semi-solid at room temperature to minimize leakage risk, and that reversibly liquefies above 90° C., so that it can be applied as a liquid during manufacturing). The assembly is sealed in an aluminum laminated heat seal pouch 247.

[0149] 25 is an exploded perspective view of a supercapacitor assembly, consisting of an interdigitated array of carbon foam electrodes 241 forming a supercapacitor, screen printed silver connector raceways 242 providing electrical current to the carbon foam electrodes 241 and covered by an electrically insulating dielectric layer 243. A polyimide sheet 244 forms the base of the assembly.

[0150] Figures 26A-H show the fabrication sequence. Figure 26A shows step 1, the fabrication of an interdigitated carbon foam electrode using a dual laser process. The enlarged area of ​​Figure 26B shows the interdigitated carbon foam electrode in more detail, with electrodes of group A forming one set of electrodes and electrodes of group B forming the other set of electrodes, and capacitive coupling between the two groups of electrodes stores energy. The approximate thickness of the carbon foam electrode is 20-30 μm.

[0151] Figure 26C shows step 2, which is the screen printing of the silver collector. One silver connector A' provides current to the electrodes of group A and silver connector B' provides current to the electrodes of group B. The approximate thickness of the silver layer is 20-40 μm and several layers can be applied.

[0152] Using a "common collector" layout, a typical interdigitated supercapacitor has two long silver collectors with graphene digits extending from one side of each of the long silver collectors. The long silver collectors exhibit significant resistance due to their length and use a significant amount of silver. Also, the curved sections of the collectors are difficult to print. The "common collector" approach shown in FIG. 26D has carbon foam digits C extending from both sides of the shared collector 242, which maximizes the space utilization of the digits, and therefore the capacitance, reduces the amount of collector material required, and eliminates difficult curved collector sections.

[0153] The areas 250 of the carbon foam digits that connect to the common collector have rounded edges which reduce the likelihood of stress fractures forming and increase the reliability of the electrical connection.

[0154] FIG. 26F shows step 3, where a dielectric layer 243 is screen printed onto the silver collectors to electrically insulate them, approximately 10-30 μm thick.

[0155] FIG. 26G shows step 4, adding copper connection tabs 245 (made from conductive metal tape) to connect to the silver collector 242. FIG. 26H shows step 5, depositing an electrolyte layer 246 onto the interdigitated carbon foam digits. The electrolyte can be a combination of hydrogel and salt (see Appendix 2). FIG. 26I shows step 6, packaging the entire assembly in an aluminum laminated heat seal pouch 247, leaving only the copper connection tabs 245 exposed. Note also that step 4, adding the copper connection tabs 245, can be done before step 2 (screen printing the silver collector) and after step 5, depositing the electrolyte layer 246 onto the interdigitated carbon foam digits.

[0156] FIG. 27 shows how a single polyimide sheet can accommodate six of these Gii-Cap assemblies of size 220mm×180mm, although other sizes (A4, A5, A6, or different from the A-series standard sizes) are possible.

[0157] The detailed Gii-Cap manufacturing process is shown in Figure 28.

[0158] The specifications for one production run of the Gii-Cap supercapacitor are shown below in Table 3, using hydrogel electrolyte. [Table 3]

[0159] It can be generalized as follows: An energy storage device, such as a supercapacitor, wherein an energy storage electrode comprises, at least in part, a carbon foam material made by the method defined in any of Features A-K above; An energy storage device, wherein screen printed electrical interconnect wiring is formed over at least a portion of each electrode, and a screen printed dielectric layer at least partially covers the electrodes and the interconnect wiring.

[0160] Feature M3: Carbon Foam Supercapacitor: Common Collector Above we saw how the "common collector" is used.

[0161] It can be generalized as follows: An energy storage device, such as a supercapacitor, wherein an energy storage electrode comprises, at least in part, a carbon foam material made by the method defined in any of Features A-K above and arranged in an interdigitated pattern; An energy storage device, wherein screen printed electrical connection wiring paths are formed over at least a portion of each electrode, with a single electrical connection wiring path connecting to underlying digits that extend vertically from both sides of the electrical connection wiring path.

[0162] Feature M4: Carbon foam supercapacitor: PPC manufacturing process PPC (Post Print Conversion) is shown in Figure 29. The process is as follows: 1. A silver collector is screen printed onto a substrate (e.g., polyimide). 2. Carbon is screen printed onto a silver collector and then allowed to dry. 3. The dielectric is screen printed onto the carbon layer and then dried. 4. A dual laser process is used to fabricate carbon foam on the carbon layer, which is attached to the underlying polyimide substrate via a non-graphene interlayer. 5. Dispense the electrolyte. 6. Add a copper / aluminum etc. tab to contact the silver collector (step 1 can be used). 7. Add lids / pouches.

[0163] All screen printing steps (1) can be done using a reel-to-reel process, then the dual laser process can be used to create the carbon foam, and then the material can be kept flat and stacked. Also, only the first laser process (sub-surface carbon material foam creation) can be done in the factory, and then the sheets are shipped to the customer, who does the second stage of the dual laser process (laser ablation) and steps 5-7.

[0164] There is an advantage to screen printing before making the carbon foam, if the carbon foam is made first it can have sharp edges and the silver screen print layer applied to those sharp edges can crack at those sharp edges, but by screen printing before making the carbon foam this issue is not there, and because the carbon foam is not dried it is not hydrophobic.

[0165] It can be generalized as follows: 1. A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, comprising: The method includes: (a) screen printing an electrical connector onto a substrate; (b) screen printing a carbon layer onto an electrical collector; (c) screen printing a dielectric onto at least a portion of the carbon layer; and (d) fabricating a carbon foam energy storage electrode at least in part by a method defined in any of Features A-K above.

[0166] Feature M5: Carbon Foam Pseudocapacitor: Metal Oxide Variant Metal oxide electrochemical deposition process (e.g., MnO for +ve) x , Fe for -ve x O x ) was used to create the Gii-Cap+ variant, which is a much higher capacitance compared to the standard Gii-Cap device (see Table 4). [Table 4]

[0167] This metal oxide electrochemical deposition process can be applied to Gii-Cap Supercap manufacturing process and even PPC process, so all Gii-Cap products can be Gii-Cap+ products. The detailed process flow chart is in Figure 29.

[0168] It can be generalized as follows: A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, comprising: an energy storage electrode comprising a carbon foam material made, at least in part, by the method defined in any of Features A-K above; The method includes applying an electrochemical deposition process of a pseudocapacitive material, such as a metal oxide, to an energy storage electrode.

[0169] Feature M6: Carbon Foam Supercapacitors: Using Ion Gel in Low Humidity Environments It uses an ion gel (ionic liquid containing fumed silica SiO2) that gives a voltage of 3V to 6V. This ion gel is solid below 90°C, so it will not leak during shipping or normal use, and is therefore particularly useful for smart labels and IoT devices; above 90°C, this ion gel liquefies and can be printed when the electrochemical printing process is above 90°C. Ion gels are typically made by adding a gel former (e.g., fumed silica SiO2) to an ionic liquid (e.g., 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4)).

[0170] Typically, fabrication is carried out in an inert (eg, argon) atmosphere since the presence of O2 and H2O can lead to voltage and stability degradation.

[0171] As detailed in Appendix 3 ("GiiCap Ion Gel"), the optimal sweet spot of O2 and HO levels that gives the best balance between increasing capacitance and decreasing voltage.

[0172] It can be generalized as follows: A method of manufacturing an energy storage device, such as a supercapacitor, comprising: an energy storage electrode comprising a carbon foam material made, at least in part, by the method defined in any of Features A-K above; A method comprising applying an ionic gel to a low humidity but non-inert environment, wherein the levels of O2 and HO in the environment are measured and controlled to optimize the capacitance of the energy storage device.

[0173] The previous sections covering Features M1-M6 explored the general characteristics of Gii-Cap carbon foam supercapacitors. The following sections covering Features N-S explore more specific products that implement Gii-Cap.

[0174] Feature N1: Conductor In devices such as the biosensor described above, it is possible and desirable to fabricate electrical conductors providing measurement signal connections from the carbon foam material made by the dual laser method, and these conductors have very low resistance, thus maximizing sensitivity. Electrodes (e.g., the biosensor working electrode that is functionalized, and the screen-printed reference and capacitor plate electrodes described above) are examples of electrical conductors covered by this feature N1. Also, electrodes whose primary function is simply to transmit signals and currents are covered by this feature N1, for example to replace conventional silver connection traces, such as the screen-printed Ag electrical connection traces described above in the biosensor.

[0175] It can be generalized as follows: A method of manufacturing an electrical conductor, the electrical conductor comprising, at least in part, a carbon foam made by the method defined in any of Features A-K above.

[0176] A conductor comprising, at least in part, a carbon foam made by the method defined in any of Features A-K above.

[0177] Feature N2: Combined sensor and supercapacitor Features L1-L4 above describe biosensors that use dual laser fabricated carbon foam for the sensor electrodes. Features M1-M6 describe supercapacitors and pseudocapacitors that use dual laser fabricated carbon foam for the electrodes.

[0178] A highly sensitive and selective biosensor can be constructed that combines both this biosensor and this supercapacitor into a single integrated device that also contains electronic circuitry to measure the variable being sensed or measured, calculate the biosensor output, and transmit the output to a POC diagnostic device or display the output on a display screen of the device (e.g., presence or absence of target, concentration of target).

[0179] 30 is a schematic cross-section through this integrated LOC device, with two separate polyimide film layers: a top layer 301 containing a functionalized carbon foam biosensor (Gii-Sens) 302 as described in Feature L, and a bottom layer 303 containing a supercapacitor 304 (Gii-Cap) as described in Feature M. Although back-to-back polyimide layers are shown, they could be side-by-side. There could be a single polyimide film that integrates the biosensor 302 and supercapacitor 304 together into a single item.

[0180] A plastic piece 305 with microchannels 306 provides a microfluidic system that distributes test fluid over the biosensor 302, a sub-surface carbon foam electrode or conventional connector wiring 307 as described in feature O leads from the biosensor to a flexible electronic device 308 (e.g., a microcontroller that measures changes in the electrochemical properties of the biosensor in the presence of the target analyte, a display panel that shows the diagnostic results, a power management system that controls power from the supercapacitor 304 to the electronic device 308). The supercapacitor 304 (Gii-Cap) is charged with power (e.g., through a wireless induction process (not shown) controlled by a microcontroller) to power the biosensor measurement process and an integrated display on which the quantitative measurement is shown. Alternatively, a rechargeable secondary battery (not shown) or a non-rechargeable primary battery (not shown) can charge the supercapacitor 304, which then powers the biosensor measurement process. Another variant is for a rechargeable secondary battery (not shown) or a non-rechargeable primary battery (not shown) to charge the supercapacitor 304 and also power the biosensor measurement process. The supercapacitor 304 is then stored to power high power processes such as wireless data transmission so that the LOC becomes a self-contained LOC device that can perform diagnostic processes and wirelessly transmit result data without the need for the user to be in close proximity to the LOC, as would be required if the LOC used traditional NFC (near field communication). The electrical connector wiring from the supercapacitor 304 to the flexible electronic device 308 is not shown.

[0181] An exploded view of the fully integrated LoC device is shown in Figure 31. Moving from the bottom layer up, there is (i) an inductive power loop 310, (ii) a Gii-Cap supercapacitor 312 that is wirelessly powered by the inductive loop 310, (iii) a Gii-Sens biosensor 313, (iv) a layer 314 with electronics for the biosensor that is powered by the supercapacitor 312 and a microfluidic channel, (v) a top panel 315 that contains a display 316 that is also powered by the supercapacitor, as well as a circular well 317 into which the sample is delivered.

[0182] FIG. 32 shows the LOC displaying quantitative results on the LOC display.

[0183] FIG. 33 shows an exploded view of an environmental monitoring device including a Gii-Sens sensor 330 configured to detect environmental parameters, such as CO2 levels, volatile organic compounds, and other air pollutants. Gii-Sens is not limited to being a biosensor, but can detect any molecule that the carbon foam sensor electrodes can be functionalized to detect. The environmental monitoring device includes the Gii-Sens sensor 330 and associated control and wireless transmission (e.g., LoRaWAN) electronics 331, as well as a PV solar cell 332 and a Gii-Cap supercapacitor 333. A secondary or primary battery (which may be a printed battery) is included in the electronics 331 and cooperates with the PV solar cell 332 to power the electronics and charge the Gii-Cap supercapacitor 333. The Gii-Sens sensor can also be configured to measure temperature, humidity, and pressure. The device has a back 334 that can be peeled off to reveal a sticky surface so that the device can be attached to a wall or the like. The PV solar cell, in conjunction with a secondary or primary battery on the electronic device 331, provides the power to charge the Gii-Cap supercapacitor 333, which in turn provides the peak bursts of power required for data transmission. Unlike current environmental monitoring devices, this device never requires battery replacement and can be permanently installed and remain in the field for many years. This device can detect air pollutants with a better signal-to-noise ratio than conventional devices. The assembled device is shown in Figure 34.

[0184] Many other types of devices can be implemented in combination with the carbon foam sensors and carbon foam supercapacitors, for example: Any biosensor that would benefit from being able to transmit data, for example wirelessly, where the data transmission is powered by a supercapacitor, for example wearable health monitoring devices such as continuous glucose monitors, other wearable monitors that sense electrolytes, potassium, sodium, lactose levels, etc. Any sensor device (i.e. not necessarily biosensors) that benefits from being able to transmit data, for example wirelessly, where the data transmission is powered by a supercapacitor. Any IoT device that benefits from being able to transmit data, for example wirelessly, where the data transmission is powered by a supercapacitor. The device may include an electronic device powered by a supercapacitor. The device may include an energy storage device and / or a battery to power and charge the electronic equipment. The device may include a PV cell for charging an energy storage device and / or a secondary battery in the device and / or power the device electronics.

[0185] It can be generalized as follows: A method of manufacturing a device including both a sensor and an energy storage device such as a supercapacitor, wherein both the sensor and the energy storage device include a carbon foam material made, at least in part, by the method defined in any of Features A-K above.

[0186] A sensor device, such as a biosensor, comprising: (a) a sensing electrode comprising a carbon foam material made at least in part by the method defined in any of Features A-K above; and (b) an energy storage device, such as a supercapacitor, wherein the energy storage device comprises, at least in part, a carbon foam material made at least in part by the method defined in any of Features A-K above.

[0187] A point-of-care diagnostic device comprising: (a) a sensing electrode comprising a carbon foam material made at least in part by the method defined in any of Features A-K above; and (b) an energy storage device, such as a supercapacitor, wherein the energy storage device comprises, at least in part, a carbon foam material made at least in part by the method defined in any of Features A-K above.

[0188] Feature N3: Combined supercapacitor and battery In this example, two different power sources are combined into a single device to form an integrated or hybrid power source, which includes a battery (e.g., printed or conventional) and a supercapacitor using carbon foam made by a dual laser method as electrodes, in a complementary manner. The battery can be a disposable, non-rechargeable battery (a "primary" battery) or a rechargeable battery (a "secondary" battery).

[0189] The power sources have complementary roles, the battery can provide slow long term charging to the supercapacitor, or powering electronic devices that consume relatively low levels of power, and the supercapacitor can provide fast, high power discharge and powering functions that require much higher levels of power (e.g., wireless data connectivity and data payload transmission functions). Note that the supercapacitor can be an EDL supercapacitor or pseudocapacitor, or any other form of energy storage device. This device can be used when occasional high power is needed (e.g., to power a transmitter to connect to a data network and transmit a data payload), but the device needs to be self-contained and last for months or years in the field, the device is a high value asset tracking label, and needs to broadcast information, but at a higher power than a traditional printed battery can provide.

[0190] A schematic diagram is shown in Figure 35. There are two separate polyimide film layers, one layer 351 containing a supercapacitor (Gii-Cap) 352 as described in feature M, and one layer 353 containing a battery 354, such as a printed battery, which may contain electrodes made using dual laser process carbon foam or conventional processes. It is also possible to fabricate the printed battery 354 and supercapacitor 352 on the same polyimide piece, although this may compromise yields, as defects in either the printed flexible battery or the supercapacitor would lead to rejection of the device.

[0191] Sub-surface carbon foam electrodes (or conventional printed electrodes) as described above lead from the supercapacitor (Gii-Cap) 352 and printed battery 354 to a BMS (battery management system) 355, which powers the flexible electronics 356, and sub-surface carbon foam electrodes or conventional connector raceways 357 connect the various parts of the flexible electronics 356. The BMS 355 controls the flow of power from the battery 354 to the electronics 356, and the battery 354 may trickle charge the supercapacitor 352. (The supercapacitor may also be a primary power source designed to be charged once at the factory and not recharged thereafter.)

[0192] The battery 354 may be a printed battery, a rechargeable secondary printed battery or a disposable non-rechargeable primary battery, which can trickle charge the supercapacitor 352 and power the sensor or other device electronics 356, which in turn powers circuitry that has short requirements for relatively high power bursts such as a data transmitter (e.g., temporary peak power). As noted above, the printed battery, supercapacitor and electronics can all be part of a single integrated device, for example all on a single substrate or all on separate attached substrates.

[0193] Although back-to-back polyimide layers are shown, they can be side-by-side, and there can be a single polyimide film that integrates the battery 354 and the supercapacitor 352 together onto a single item.

[0194] The battery 354, supercapacitor 352, and electronic device 356 may all be formed on one or more substrates as part of a continuous or batch manufacturing process (e.g., without taking a previously manufactured battery and combining it with a supercapacitor). This allows the interconnects to be built as an integral part of the manufacturing process, leading to lower cost, faster manufacturing, and better performance (e.g., if the interconnects are shorter).

[0195] The device can be used in a smart label (see below), or an IoT environmental monitoring device (e.g., a temperature or humidity sensor), a train seat occupancy sensor, a medical monitoring device (e.g., a continuous blood glucose monitor). More generally, the device may include electronics powered by a battery, the device may include electronics powered by a supercapacitor, the device may include a data transmitter powered by a supercapacitor, the battery may be a printed battery, and the battery may be a primary or secondary battery.

[0196] It can be generalized as follows: A method of manufacturing an integrated device including a battery and a supercapacitor, wherein the battery provides long term power and the supercapacitor provides short term power at a level higher than the battery, and the supercapacitor comprises, at least in part, a carbon foam material made by a method defined in any of Features A-K above.

[0197] An integrated device including a battery and a supercapacitor, wherein the battery provides long term power and the supercapacitor provides short term power at a level higher than the battery, the supercapacitor comprising, at least in part, a carbon foam material made by a method defined in any of Features A-K above.

[0198] Feature N4: Smart Label One important application is a smart label shown in FIG. 36 with a bottom side shown on the left and an exposed label surface 363 with human readable text shown on the right, the label includes an adhesive release liner 364 so that the bottom side can be attached to a package, component, etc. The label includes a thin flexible battery 360 printed on a polyimide film and then a Gii-cap supercapacitor 361 formed on the same polyimide layer (or a different polyimide layer bonded to the printed battery polyimide film). The thin flexible battery can be a non-rechargeable primary battery or a rechargeable secondary battery. The supercapacitor powers the data transmitter and the printed battery powers the smart label electronics including the sensor and power management electronics. The smart label includes human readable printed information 363 on one surface and the back side includes ...

[0199] The smart label includes an electronic module 362 with power management, sensors (e.g. solid state vibration, temperature, pressure, GPS, etc. sensors), and data transmission electronics such as an LTE transmitter, or an ultra-low-cost LoRaWan transmitter. The supercapacitor 361 provides enough peak power to transmit a useful data package once a data connection is established, so there is no need to simply include this data in the "advertisement" signal; instead, the smart label can establish a data connection with a data receiver and then transmit the data payload once the connection is established, and thus can have reasonable assurance that the data was received. More generally, the device may include electronics powered by a battery, the device may include electronics powered by a supercapacitor, the device may include a data transmitter powered by a supercapacitor, the battery may be a printed battery, the battery may be a primary or secondary battery.

[0200] For scalable manufacturing (e.g., producing millions of smart labels at low cost), reel-to-sheet manufacturing of smart labels is desirable (see Feature P:Gii3 below).

[0201] It can be generalized as follows: A smart label comprising a battery and a supercapacitor, the battery providing long term power and the supercapacitor providing short term power at a level higher than that of the battery, the supercapacitor comprising a carbon foam material made at least in part by a method defined in any of features A-K above; A smart label includes electronics, such as sensor electronics powered by a battery and a data transmitter powered by a supercapacitor.

[0202] Feature N5: Combined Supercapacitor and Antenna The supercapacitor from the previous example of feature M can power the antenna but cannot be integrated with a battery, for example this supercapacitor can be powered from a solar cell or can extract power from a local WiFi or wireless charger (e.g. Qi standard).

[0203] It can be generalized as follows: A method of manufacturing an integrated device comprising an antenna and a supercapacitor, the supercapacitor powering the antenna and comprising, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0204] An integrated device comprising an antenna and a supercapacitor, the supercapacitor powering the antenna and comprising, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0205] Feature N6: Combined energy scavenger + supercapacitor. One useful feature is to combine an energy scavenger with a carbon foam supercapacitor into a device. The energy scavenger can be a solid-state energy harvester such as a solar cell, or a vibration energy harvester (e.g., piezoelectric fiber-based), or a thermoelectric generator (e.g., a Seebeck generator). The supercapacitor can provide power (e.g., temporary power) to circuits that have short requirements for relatively high power bursts, such as data transmitters and antennas. The device may include a primary battery (e.g., a non-rechargeable printed battery) or a secondary rechargeable battery.

[0206] The energy scavenger can be on the same substrate as the supercapacitor or on a separate but connected substrate, and the supercapacitor can be on the same side as the energy scavenger or on the opposite side.

[0207] If a battery is included in the device (e.g., a printed rechargeable secondary battery), the energy harvester charges the battery, which powers the low-power subsystem (e.g., a sensor), and also charges the supercapacitor, which provides temporary high power for data transmission. Alternatively, the energy harvester can directly charge the supercapacitor.

[0208] This approach can be used for smart labels (see below), or IoT environmental monitoring devices (e.g. temperature or humidity sensors), train seat occupancy sensors, wearables, medical monitoring devices (e.g. continuous blood glucose monitors). This approach is particularly useful when devices need to be powered continuously (or with high regularity), for example when continuous monitoring of the environment or personal health is required.

[0209] The device may include a LoRaWan or other ultra-low power transmitter. The supercapacitor may provide enough peak power to transmit a useful data package once a data connection is established, so this data does not simply need to be included in the advertising signal; instead, the smart label may establish a data connection with a data receiver and therefore be assured that the data is received.

[0210] More generally, the energy scavenger may be a solid-state energy harvester such as a solar cell, or a vibration energy harvester (e.g., piezoelectric fiber based), or a thermoelectric generator (e.g., a Seebeck generator), the device may include one or more sensors powered by the energy scavenging, the energy scavenger may charge a supercapacitor, the device may include a primary or secondary battery, the device may be a smart label, or an IoT environmental monitoring device (e.g., a temperature or humidity sensor), a train seat occupancy sensor, a wearable, or a medical monitoring device.

[0211] It can be generalized as follows: A data logging device comprising an energy scavenger system and a supercapacitor, the supercapacitor powering an antenna and comprising, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0212] Feature O1: 3D Carbon Foam Construction: Gii-Thru for Gii-Cap In the previous section, the carbon foam in the Gii-Cap supercapacitor is formed into a single planar layer of interdigitated graphene foam digits. In this section, we describe a three-dimensional structure of carbon foam that allows the carbon foam supercapacitor electrodes to be formed as parallel plates in a 3D structure, with energy storage in some cases greater than a single layer of interdigitated graphene foam digits.

[0213] Figure 37 shows the basic layering of the various materials in the core structure. Multiple screen printing steps are performed on a sheet of PI polyimide film 371. First, a conductor such as a carbon ink or carbon paste layer 372 is screen printed on the bottom surface of the polyimide film 371. Then a collector 373, for example a screen printed silver collector, is screen printed on the carbon layer 372. Then a dielectric layer 374 is screen printed on the collector.

[0214] 38 shows a carbon foam layer formed on a polyimide film 371 using the dual laser process described above, more specifically, the IR laser forms an encapsulated carbon foam layer 375 on the PI film 371 beneath which is a disordered amorphous non-graphene layer 376 formed on the underside of the PI film 371. The CO2 ablation laser exposes the previously encapsulated carbon foam layer 370, imparting a unique morphology to the exposed surface layer 377.

[0215] This structure provides a conductive path from collector layer 373, through conductive ink or paste layer 372, through the disordered amorphous non-graphene layer 376, and then to carbon foam layer 375. In this way, the electrical potential can be raised over a large area of ​​carbon foam 375, allowing it to act as a capacitive plate, with this structure forming part of a half cell.

[0216] Typical thicknesses are as follows: polyimide film 371: 127 μm, carbon ink layer: 20 μm; silver collector layer 373: 30 μm, dielectric layer: 40 μm, carbon foam layer 375 and disordered amorphous non-graphene layer 376: 127 μm, intrinsic surface morphology layer 377: 25 μm.

[0217] Gi-Cap+ (metal oxide electrochemical deposition process (e.g., MnO for +ve) x , Fe for -ve x O x It should be noted that a variant using the Gii-Thru 1.0 - see feature M2 above) and offering a much higher capacitance compared to the standard Gii-Cap device can be used with the Gii-Thru 1.0 - see feature M2 above.

[0218] It can be generalized as follows: An energy storage device, such as a supercapacitor, comprising: (i) a carbon precursor film; (ii) a screen printed conductive paste or conductive ink layer on the surface of the carbon precursor film; (iii) a screen printed collector layer over the screen printed conductive paste or conductive ink layer; (iv) a screen printed dielectric layer on the collector layer; (v) an energy storage electrode comprising a carbon foam material made at least in part from a carbon precursor film by the method defined in any of Features A-K above, wherein a conductive path is formed from the carbon foam material to the collector layer through a conductive paste or conductive ink layer.

[0219] Features O2: 3D carbon foam construction: Gii-Thru stackable Gii-Cap / Gii-Cap+ Several structures as described in FIG. 38 can be stacked on top of each other, and since the surface area of ​​the carbon foam layers can be large (significantly larger than the surface area of ​​the digits of the planar interdigitated supercapacitor described above), this allows high performance supercapacitors to be produced.

[0220] A half cell is shown in FIG. 39. The half cell includes a hydrogel electrolyte layer 390, a carbon foam layer 391 with a unique surface morphology on the PI film 392, a screen printed carbon paste layer 393, a screen printed silver connector layer 394 with external copper tab 395 connection points, a screen printed dielectric isolation layer 396, a second carbon foam layer 397 with a unique surface morphology on the PI film 398, and a hydrogel electrolyte layer 399 at the base of the stack. This may help to relate this structure to the schematic in FIG. 38. In FIG. 40A, the four main layers shown in FIG. 38 are grouped together in A, namely, moving down through the stack, the carbon foam layer, then the carbon ink layer, then the silver collector layer, then the dielectric layer. FIG. 40B is a cross section through the structure of FIG. 40A showing the features of group A. FIG. 40B is the same cross section, but this time labeling all of the elements of FIG. 39.

[0221] The full cell is shown in Figures 41A and 41B. In Figure 41A, only features that are also present in Figure 39 are labeled (using the same numbering). Thus, the full cell includes a hydrogel electrolyte layer 390, a carbon foam layer 391 with unique surface morphology in a PI film 392, a screen printed carbon paste layer 393, a screen printed silver connector layer 394 with external copper tab 395 connection points, and a screen printed dielectric isolation layer 396.

[0222] In Figure 41B, additional layers are now added. Moving sequentially down through the structure, there is a screen printed dielectric isolation layer 400, then a screen printed silver collector layer 401 with copper tabs 402, then a screen printed carbon paste layer 403, then a carbon foam layer 404 with a unique surface morphology in the PI film 405.

[0223] In Figure 41C, the four main layers shown in Figure 38 are grouped together in A, and the four top layers are in the reverse order and grouped together in B. Groups A and B are separated by a hydrogel (e.g., polymer hydrogel) electrolyte layer 399 that is dispensed using a conventional electrolyte dispensing system.

[0224] Figure 41D is a cross section through this structure showing the Group A and Group B layers separated by a hydrogel (e.g., polymer hydrogel) electrolyte layer 399. Figure 41E is the same cross section, but this time the individual layers are numbered according to the schematic in Figure 38.

[0225] FIG. 41F is a perspective view of the assembled supercapacitor.

[0226] Figure 42 shows a four-stack of full-cell supercapacitors, with the carbon foam layer shown in A and the polymer hydrogel electrolyte shown in B. Additional cells can be added to the stack to give the required performance.

[0227] FIG. 43A shows a detailed manufacturing flow of the Gii-Thru supercapacitor, and FIG. 43B shows a detailed manufacturing flow of the Gii-Thru multi-stack supercapacitor.

[0228] It can be generalized as follows: An energy storage device, such as a supercapacitor, comprising: (i) a carbon precursor film; (ii) a screen printed conductive paste or conductive ink layer on the surface of the carbon precursor film; (iii) a screen printed collector layer over the screen printed conductive paste or conductive ink layer; (iv) a screen printed dielectric layer on the collector layer; (v) an energy storage electrode comprising a carbon foam material made at least in part from a carbon precursor film by the method defined in any one of Features A-K above, wherein a conductive path is formed from the carbon foam material through a conductive paste or conductive ink layer to a collector layer; An energy storage device, wherein a plurality of subassemblies are formed into a stack, with adjacent energy storage electrodes separated by an ion gel electrolyte.

[0229] Feature O3: 3D Carbon Foam Construction: Gii-Thru for Gii-Sens: HISLOC The Gii-Thru structure described in FIG. 38 can be used not only in supercapacitors but also in Gii-Sens sensors such as biosensors.

[0230] For microfluidics, the Gii-Thru HISLOC (High Sensitivity Low Cost) platform approach allows for the liquid and carbon foam sensor to be on the top surface of the biosensor device, and the electrical connections that connect to the carbon foam sensor to be on the bottom surface of the biosensor device. Microfluidics traditionally uses functionalized gold electrodes where the electrical connectors that connect to the functionalized gold electrodes are all coplanar, and the Gii-Thru biosensor has cost, yield, and performance advantages over these functionalized gold electrodes. Also, moving the electrical connections to the bottom or base of the biosensor allows for greater miniaturization and compatibility with POC (point-of-care) systems.

[0231] 44A is a schematic cross-sectional view through a Gii-Thru sensor used in a three-sample array microfluidic diagnostic device. At the top are three sample wells 440 into which the fluid to be analyzed flows. The wells 440 are formed as small openings in a laminated well spacer layer 441 that sits on a polyimide film layer 442.

[0232] Polyimide film layer 442 has three functionalized carbon foam regions formed therein that form a reference electrode 448A, a working electrode 448B, and a counter electrode 448C, with the top surface of each electrode 448A-448C exposed to the analyte fluid present in well 440. The base of the reference electrode 448A may include an Ag-AgCl layer (or a screen printed carbon layer) 449, the base of the working electrode 448B has a screen printed conductive carbon layer 443, and the base of the counter electrode 448C has another screen printed conductive carbon layer 443. In this manner, the reference electrode 448A is in electrical contact with reference electrode connection 444A, the working electrode 448B is in electrical contact with working electrode connection 444B, and the counter electrode 448C is in electrical contact with counter electrode connection 444C.

[0233] A screen printed dielectric layer 447 forms the base of the structure.

[0234] Thus, what is interesting about this structure is that the electrode connections 444A-C are not coplanar with the functionalized carbon foam electrodes 448A-C, as they would be in a conventional screen printed sensor. Instead, the electrode connections 444A-C are in a plane below the functionalized carbon foam electrodes 448A-C, on the opposite side from the well 440. This structure allows for miniaturization and improved compatibility with point-of-care (POC) systems.

[0235] FIG. 44B shows an isometric exploded view of the microfluidic diagnostic device of FIG. 44A. Three sample wells 440 are located in a laminated well spacer layer 441 that is located on a polyimide film layer 442. A reference electrode 448A, a working electrode 448B, and a counter electrode 448C are shown, with the end of the reference electrode 448A covered by an Ag-AgCl layer or a screen printed carbon layer 449, and the working electrode 448B and the counter electrode 448C covered by a screen printed conductive carbon layer 443. As discussed above, the reference electrode 448A is in electrical contact with the reference electrode connection 444A, the working electrode 448B is in electrical contact with the working electrode connection 444B, and the counter electrode 448C is in electrical contact with the counter electrode connection 444C.

[0236] Note that the three functionalized carbon foam regions 448A-C are shown as planar rectangles residing in different planes, however this is merely an artifact of the CAD used to create the drawing, and the carbon foam regions 448A-C are better represented in Figure 44 A. A screen printed dielectric layer 447 forms the base of the structure.

[0237] 44A and 44B above show a 3-spot array microfluidic diagnostic device. In Fig. 45A and 45B, an 8-spot array microfluidic diagnostic device is shown. In isometric view 45A, a laminated well spacer 451 includes an array of eight analyte wells 452 for working electrodes, plus a well 453 for a counter electrode and a well 454 for a reference electrode, and the laminated well spacer 451 sits on a polyimide layer 455. Gii carbon foam in polyimide layer 456 forms eight working electrodes 457 and a counter electrode 458, and is made using a dual laser process. Note also that the carbon foam electrodes 457, 458 are shown as planar rectangles residing in three different planes, but this is merely an artifact of CAD and the carbon foam forms a continuous region in the polyimide layer 455.

[0238] The reference electrode 459 is covered with a thin screen printed Ag-AgCl layer. A thin screen printed carbon connection interface layer 460 underlies the working electrode 457 and counter electrode 458, and screen printed silver connection traces 461 make electrical connections to all of the electrodes 457, 458, and 459. A screen printed dielectric layer 462 then forms the case of the device. Figure 45B is a pair of overhead views of the device of Figure 45A, with the lower view showing the underlying connection trace paths.

[0239] FIG. 46A shows a perspective view of the fully assembled multi-sample array microfluidic diagnostic device, and FIG. 46B shows an overhead view.

[0240] It can be generalized as follows: A microfluidic diagnostic device including a sample well positioned on a top surface of the device, wherein reference, working, and counter electrodes made at least in part from a carbon precursor film by a method defined in any of Features A-K above are in a layer below the sample well, and connections for the reference, working, and counter electrodes are in a layer below the reference, working, and counter electrodes.

[0241] FIG. 47A shows an exploded view of a microfluidic diagnostic device consisting of multiple laminated layers as shown in FIG. 44A, which includes a Gii-Thru implemented 3-spot array (3SA) microfluidic biosensor. The top layer 470 of the device is a microfluidic foil, the middle layer 471 is a microfluidic foil with adhesive and includes printed or molded microfluidic channels 472, and the bottom layer 473 is a microfluidic foil with adhesive. The Gii-Thru sensor 474 is a 3-spot array (3SA) biosensor and includes a connector 475. FIG. 47B is an overhead view showing the internal structure. The Gii-Thru sensor 473 can be replaced with a different biosensor (e.g., 8SA) for greater flexibility.

[0242] FIG. 48B shows an exploded view of a microfluidic diagnostic device consisting of a printed or molded microfluidic card as shown in FIG. 44A, which includes a 3-spot array (3SA) microfluidic biosensor with Gii-Thru. The device includes a clear resin barb connector 481, a top foil 482, a clear resin molded microfluidic card 483 with microfluidic channels 484, a well unit 485 made of microfluidic foil with adhesive, and a Gii-Thru sensor 486. Again, the Gii-Thru sensor 486 can be replaced with a different biosensor (e.g., 8SA) for greater flexibility, and the molded microfluidic card 483 can be replaced with differently designed microfluidic features to allow for different assay platforms. FIG. 45B shows an overhead side view.

[0243] Feature O4: 3D Carbon Foam Construction: Gii-Thru for Gii-Sens: HISLOC Manufacturing Process The HISLOC manufacturing process can be summarized as follows: 1. Screen print a layer of carbon onto the underside of a polyimide film. 2. Screen print the silver connections. 3. Screen print a silver / silver chloride reference electrode (steps 3 and 4 can be reordered with 4 followed by 3). 4. Screen print the dielectric. 5. Fabricating Gii carbon foam sensor electrodes on polyimide films using a dual laser process.

[0244] A detailed manufacturing process flow is shown in Figure 49. It can be generalized as follows: A lab-on-a-chip device, comprising: (i) a carbon precursor film; (ii) a screen printed conductive paste or conductive ink layer on the surface of the carbon precursor film; (iii) a screen printed conductive layer over the screen printed conductive paste or conductive ink layer; and (iv) a screen-printed reference electrode; (v) a screen printed dielectric layer on the collector layer; (vi) a subassembly comprising: a sensor electrode comprising a carbon foam material fabricated at least in part from a carbon precursor film by a method as defined in any of Features A-K above, wherein a conductive path is formed from the carbon foam material to the conductive layer via a conductive paste or conductive ink layer.

[0245] Group 4 Feature P: Scalable Manufacturing: G-ii3 Gii-3 is a scalable manufacturing facility with reel-to-reel or reel-to-sheet production of all of the Gii-based materials mentioned above. A key commercial advantage is that Gii3 manufacturing does not require custom equipment; it uses commercially available computer-controlled lasers for dual laser carbon foam manufacturing and conventional screen printing and drying techniques, which are well-known and well-understood manufacturing processes and equipment, leading to repeatability and reliability.

[0246] FIG. 50 is a schematic diagram of the overall manufacturing process, and FIG. 51 shows the detailed process flow.

[0247] It can be generalized as follows: 1. A method of manufacturing a device including one or more electrodes, each comprising a carbon foam material, comprising: The method includes continuously winding a carbon precursor film through a series of operations required to produce a carbon foam material made at least in part by the method defined in any of Features A-K above.

[0248] Feature Q: Various other Gii uses The Gii carbon foams described herein can be used in a wide variety of applications, including many applications for which traditional graphene foams have been considered suitable.

[0249] It can be generalized as follows: A device comprising a carbon foam material made at least in part by the method defined in any of features A-K above, wherein the device is one of the following types of devices: Hall Effect Sensors: Carbon foam exhibits a response to a magnetic field. For example, a prototype sensor is shown that uses Gii carbon foam with polydimethylsiloxane (PDMS) embedded in and on the structure as the active layer of a piezoresistive pressure sensor for use in robotic touch sensing applications, where several layers of carbon foam can exhibit sensitivity to pressure with a sensitivity of 0.0418 mV / kPa over the range of 0 to over 50 kPa. See DOI:10.4028 / p-oy94hj. and DOI:1109 / CDE52135.2021.9455738, the contents of which are incorporated by reference to the fullest extent permitted. Infectious disease sensors. · Gii carbon foam undergoes π-π non-covalent functionalization with pyrene carboxylic acid (PCA) for detection of interleukin-10 inhibition, a biosensor. See DOI: 10.1016 / j.bios.2022.114954, the contents of which are incorporated by reference to the maximum extent permitted. -Continuous monitoring of chemical sensors. Glucose monitoring sensor: A reversible polymer displacement sensor mechanism for electrochemical glucose monitoring is demonstrated in which a pyrene-derivatized boronic acid chemo-receptor for glucose is adsorbed on a carbon foam electrode where it competitively binds with polynordihydroguaiaretic acid. See DOI:10.1039 / D1AN01991K, the contents of which are incorporated by reference to the maximum extent permitted. Lactate sensor: A synthetic organic receptor molecule is used based on boronic acid bound to carbon foam to provide functionality and selectivity in competitive analyte binding using surface redox polymer label substitution. See DOI: 10.1016 / j.snb2022.133089, the contents of which are incorporated by reference to the fullest extent permitted. Gas detection sensors such as hydrogen peroxide and oxygen detection, oxygen detection using Gii carbon foam soaked in pH 7 nanoparticle polymeric phosphate buffer of intrinsic microporosity (PIM-1). See DOI:10.1016 / j.elecom.2022.107394, the contents of which are incorporated by reference to the maximum extent permitted. Optical detector. Self-charging hybrid power generation devices. ·Green gas conversion into useful chemicals. Fuel cells, e.g. hydrogen fuel cells. · Filters including gas permeable filters. Heating devices.

[0250] Feature R: Non-graphene carbon material foam Conventional graphene foam appears under a scanning electron microscope to have large, open ring structures that are typically 500 μm in size. Carbon foam produced using the dual laser process looks very different, and Figures 52-57A are SEM images of this Gii carbon foam.

[0251] Figure 57B is an SEM of carbon nano-onions, see "Raman spectroscopy of polyhedral carbon nano-onions", DOI:10.1007 / s00339-015-9315-9 and further "Carbon nano-onions: unique carbon nano-structures with fascinating properties and their potential applications", DOI:10.1016 / j.ica.2017.07.021. The similarities with Gii carbon foams are clear.

[0252] As mentioned earlier, graphene foam has several properties, it is hydrophobic and has low wettability. Raman analysis of a typical graphene foam reveals the following signatures: absence of D peak, 2D peak higher than G peak, and peak D:peak G ratio close to zero. However, carbon foam produced using the dual laser process does not share any of these characteristics, it is hydrophilic with a contact angle less than 20°, it lacks the characteristic Raman spectral signature of graphene, it shows a prominent D peak, 2D peak significantly less than G peak, and peak D:peak G ratio significantly above zero. Figure 58 shows the Raman shifts of eight sheets of carbon foam made using the dual laser process, showing the consistency of the Raman signatures. Also, the carbon foam material shows a prominent D peak, 2D peak less than G peak, and peak D:peak G ratio above zero. As mentioned earlier, this Raman spectrum has much in common with carbon nano-onions, see also Figure 18C from "Raman spectroscopy of polyhedral carbon nano-onions", DOI:10.1007 / s00339-015-9315-9. The specific dual laser parameters used to create this low electrical resistivity carbon nano-onion variant of Gii carbon foam are in Table 5 below. [Table 5]

[0253] It can be generalized as follows: A hydrophilic carbon foam material made at least in part by the method defined in any of Features A-K above, and having a contact angle of less than 20°.

[0254] A carbon foam material made at least in part by a method as defined in any of Features A-K above, and having a Raman spectrum exhibiting a prominent D peak, wherein the 2D peak is smaller than the G peak, and wherein the Peak D:Peak G ratio is greater than zero.

[0255] A carbon nano-onion material made at least in part by the method defined in any of Features A-K above.

[0256] It should be noted that any of the devices previously mentioned, e.g., sensors, pressure sensors, biosensors, Hall effect sensors, supercapacitors, hydrogen fuel cells, filters, may be characterized by the use of these materials and thus can be generalized to the following: A device comprising a carbon foam material made at least in part by the method defined in any of Features A-K above, and which is hydrophilic with a contact angle of less than 20°.

[0257] A device comprising a carbon foam material made at least in part by a method as defined in any of Features A-K above, and having a Raman spectrum exhibiting a prominent D peak, wherein the 2D peak is smaller than the G peak, and wherein the Peak D:Peak G ratio is greater than zero.

[0258] A device comprising a carbon nano-onion material made at least in part by the method defined in any of Features A-K above.

[0259] Appendix 1 Implementation of a supercapacitor with a hydrogel electrolyte Appendix 2 Gii-cap+hydrogel Appendix 3 GiiCap Ion Gel Appendix 4. Gii-Sens® Assay Feasibility Proposal for a 3-Month Period Appendix 5. Sensor implementations in which receptors are bound to 3D carbon foam materials via linkers Appendix 6 Benchmark Experiment Conditions: Appendix 7 Optimization of surface immobilization of anti-human procalcitonin (cAb) Please note that Appendices 1-7 describe specific implementations of Gii carbon foam. Appendix 8 Consolidated list of features and optional features Appendix 1. Supercapacitor implementation with hydrogel electrolyte

[0260] [Background technology] A supercapacitor is a device that stores electric charge. In terms of their construction and function, supercapacitors lie between electrolytic capacitors and rechargeable batteries.

[0261] The properties of supercapacitors make them superior to rechargeable batteries in applications where short charging times are required, as well as in applications where a large number of charge / discharge cycles are used. Disadvantages of supercapacitors compared to batteries include a lower ability to store energy for long periods of time.

[0262] The operating limits of a supercapacitor are imposed by the material properties of the components. In particular, the maximum voltage at which a supercapacitor can operate, i.e., the maximum voltage at which the supercapacitor can be charged, depends on the stability of the electrolyte and / or electrodes. The maximum voltage of a capacitor is an important parameter, especially as the amount of energy stored by a capacitor is proportional to the square of the voltage. Supercapacitors with organic electrolytes generally support higher voltages than supercapacitors with aqueous electrolytes. By utilizing organic electrolytes, supercapacitor designers can build devices with an operating range of 2.5-2.7 V. In contrast, aqueous electrolytes are often preferred for reasons of cost reduction and reduced toxicity, but generally build devices with a lower operating voltage range. Known symmetric aqueous supercapacitors generally cannot support voltages higher than 1.3-1.5 V. If electrodes of different materials are used, this voltage limit can reach 1.8-2.0 V. The limitations of aqueous-based supercapacitors are due to the electrolysis of water, which in principle occurs when exposed to a potential difference of 1.23 V. In practice, however, large potential differences are required before electrolysis can occur to overcome the effects of overpotentials.

[0263] Carbon-based electrodes have been associated with supercapacitors since the early days of their development. Initially, carbon attracted interest as an electrode material because it offered the possibility of producing electrodes with large surface areas. It was not until later in the development of supercapacitor devices that the importance of the so-called double layer at the electrode surface was recognized. This complex and often poorly understood phenomenon associated with the use of carbon as an electrode material is at the heart of the high capacitance values ​​associated with supercapacitors. Supercapacitor devices that include carbon-based electrodes are believed to involve a double layer at the electrode surface, and energy is stored electrostatically. Such supercapacitors are referred to as electrostatic double layer capacitors, or EDLCs.

[0264] There are other categories of supercapacitors. Electrochemical pseudocapacitors utilize metal oxide electrodes or conducting polymer electrodes. In contrast to the electrostatic charge storage mechanism of EDLCs, charge storage in pseudocapacitors is primarily electrochemical. A third type of supercapacitor is the hybrid capacitor. Hybrid capacitors have asymmetric electrodes. One electrode is typically carbon and has electrostatic charge storage properties, while the other electrode is typically a lithium-containing or lithium-doped material and exhibits primarily electrochemical charge storage properties.

[0265] Traditionally, a supercapacitor can be thought of and is modeled as a series connection of two capacitors, one associated with each electrode. Each capacitor is located at the interface between the electrode and the electrolyte and is formed from a supercapacitor electrode, a dielectric layer formed from solvent molecules present in the electrolyte (called the inner Helmholtz plane), and a layer of charge carriers provided by the electrolyte as a counter charge for charging on the electrode (called the outer Helmholtz plane). This triple structure of electrode, inner Helmholtz plane, and outer Helmholtz plane that forms a capacitance system for each electrode is called a double layer, or electric double layer.

[0266] [Summary of the Invention] A first aspect of the feature provides a symmetric supercapacitor device comprising two electrodes, each electrode comprising carbon foam as described herein (see, e.g., Features A-K of Appendix 8), and an ionic gel or hydrogel electrolyte encapsulating the electrodes at an active area.

[0267] It has been discovered that a symmetric supercapacitor device, with the combination of the above features, produces an enhanced operating voltage window. By calling the device symmetric, it is meant that the electrodes can include and be constructed from the same material.

[0268] The operating voltage window, or window of operation, of a supercapacitor is a key parameter of such devices and is determined by the breakdown voltage of the electrolyte. For aqueous electrolyte-based supercapacitors, the breakdown of water is generally responsible for limiting the operating voltage window.

[0269] The reasons for the unexpectedly large operating window observed in the devices of the present disclosure are not fully understood, and without being bound by any theory, it is apparent that the exceptional properties are the result of the combination of the carbon foam electrodes and the electrolyte, and in particular the interface between these elements.

[0270] The large operating window of the device equates in electrochemical terms to an unexpectedly large overpotential at the electrode. An overpotential is the potential difference beyond the thermodynamic redox potential for a particular reduction / oxidation reaction required for that reaction to occur. Overpotential is generally a poorly understood phenomenon, as many factors contribute to it. For example, overpotential depends on the electrode material, electrode morphology, and the nature of the electrolyte. In this feature, it is believed that the large surface area presented to the electrolyte by the carbon foam electrode likely plays a role in the performance of the device. How ions diffuse from the bulk of the electrolyte to the electrode surface, and the associated depletion of charge carriers at the electrode surface, are known to affect overpotential. This may play a role in the device. The diffusion rate of charge carriers in the electrolyte may be affected by the presence of hydrated ions, which are larger in size than non-hydrated ions. There may also be an effect on the overpotential resulting from interactions between the charge carriers and the morphology of the carbon foam electrode. It is also believed that the presence of ion gel or hydrogel polymers also affects the diffusion of charge carriers to the electrode surface, possibly sterically and related to the carbon foam morphology.

[0271] Hydrogels are gels whose liquid component is water and which may be formed from a network of polymer chains. A supercapacitor whose dielectric is formed by a hydrogel electrolyte is expected to have performance characteristics associated with aqueous electrolyte-based supercapacitors. However, contrary to this expectation, the inventors have found that the performance of a supercapacitor according to the first embodiment, i.e. a symmetric device, in which the electrodes are of the same material, these electrodes comprising carbon foam and encased in a hydrogel electrolyte, exceeds the expectations of an aqueous-based device. The operating voltage window of the device is unexpectedly enhanced compared to an aqueous electrolyte-based device. The window of operation is similar to organic solvent-based supercapacitors.

[0272] Polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), sodium polyacrylate, acrylate polymers, and copolymers rich in hydrophilic groups are examples of polymers that may be utilized in the hydrogel. Fluorinated hydrogels may be used. The combination of hydrogels with ionic charge carriers helps achieve the surprisingly large operating window achieved by the present system.

[0273] The electrodes of the devices of the present disclosure are located on a substrate and the electrolyte is present over the electrodes in a manner that encapsulates at least a portion of the electrode structure, thus forming an active area. The active area of ​​a supercapacitor is the area of ​​the supercapacitor that includes the electrolyte and electrodes where charge is stored.

[0274] The electrodes of the device may have an interdigitated geometry, i.e., the electrodes may be interdigitated. The interdigitated electrode geometry helps maximize the capacitance of the supercapacitor. The interdigitated electrode geometry also enables separator-less devices. Supercapacitors typically include a separator between opposing electrodes to prevent short circuits between the electrodes. The absence of a separator facilitates the construction of supercapacitor devices. Separators can also adversely affect device performance, for example, by impeding charge flow leading to reduced charge / discharge rates. The absence of a separator avoids these negative performance effects.

[0275] Interdigitated electrode geometries are well suited for symmetrical devices. If the materials of the opposing electrodes are different than when the electrodes are of the same material, it is obviously more complicated to construct an interdigitated electrode geometry. If the electrodes are of the same material, they can be manufactured in one method step, possibly in situ. If different electrode materials are used, multiple manufacturing steps are required, significantly complicating the manufacturing process.

[0276] The absence of a separator further eliminates the negative effects that a separator can have on device performance, such as impeding charge flow leading to slower charge / discharge rates.

[0277] The hydrogel electrolyte may contain a sufficiently high concentration of charge carriers to produce this enhanced operating voltage window.

[0278] The enhanced operating voltage window may depend on the concentration of charge carriers.

[0279] The charge carriers may have a redox potential that supports an enhanced operating voltage window.

[0280] The charge carriers may be provided by an aqueous solution of an acid, an aqueous solution of an alkali, or an aqueous solution of a salt. Acids that may be used include sulfuric acid. Alkalis that may be used include potassium hydroxide.

[0281] The hydrogel electrolyte may comprise a mixture of a hydrogel and a salt. The electrolyte may be composed of a hydrogel, where the hydrogelling polymer may be, for example, PVA or PVP. The salt may be, for example, NaClO4 or NaNO3 or Mg(ClO4)2. The molarity of the salt may be, for example, 0.5M or more, such as 1M or more, such as 2M or more, such as 2.5M or more, such as 3M or more, for example about 5M. The molarity of the salt may be, for example, 1M to 10M, or the molarity of the salt may be, for example, 2.5M to 7.5M.

[0282] Salts that can be used include phosphonium salts, perchlorates, nitrates, and arsenates. Examples of salts include sodium sulfate, sodium disulfate, sodium persulfate, sodium perchlorate, lithium perchlorate, magnesium perchlorate, sodium nitrate, and lithium hexafluoroarsenate. Aqueous solutions of these salts can be used in the electrolyte to provide ion carriers.

[0283] The charge carriers may be ions. The charge carriers may be hydrated ions.

[0284] Hydrated ions are ions in an aqueous environment. Polar water molecules arrange around the ion, forming a hydration sphere with the ion at the center. The details of the mechanism behind the surprisingly wide enhanced operating voltage window observed in this feature are not well understood, and the inventors do not wish to be bound by theory. Nevertheless, the surprising and advantageous properties of the device are the result of a synergistic effect between the electrodes and the dielectric material. The enhanced performance is an expression of the lack of water splitting under voltage conditions where one skilled in the art would expect electrolysis to occur. The interface between the electrode and the electrolyte is expected to be at the origin of the performance. There may be a synergistic interaction between the size of the charge carriers, possibly hydrated, and the size of the pores present in the electrode. Hydrogels contain a network of polymer chains, and this chain network of hydrogels may also have a physical (steric) effect that limits the exposure of water molecules to potential differences that may cause their splitting.

[0285] It is believed that the increased size of the hydrated ions, combined with the porous structure of the carbon foam electrode, hinders diffusion close to the electrode surface, resulting in an increased overpotential.

[0286] The electrodes of the symmetric supercapacitor device may include porous carbon foam. Optionally, the electrodes may not include an added binder material.

[0287] It is believed that the porous carbon foam electrodes couple with charge carriers in the electrolyte and increase the overpotential, thereby improving the operating window of the supercapacitor.

[0288] Carbon foam consists of one or more 2D carbon sheets (each sheet is a layer of sp2 bonded carbon) that are folded over each other to form a three-dimensional structure rather than a planar sheet. Carbon foam lacks the usual AB stacking of planar carbon sheets found in graphite or multi-layered 2D carbon. Carbon foam materials are typically porous. Carbon foams have a high surface area. The porosity of the carbon foam, and therefore the surface area of ​​the foam, can be controlled by various parameters of the growth method. This has the advantage that the porosity of the electrodes of the device can be controlled during the electrode fabrication process.

[0289] The carbon foam electrode may be on a substrate. The carbon foam electrode may be on a polyimide substrate. The polyimide substrate may be polyimide. The substrate may form the substrate of a supercapacitor device. The substrate may be thin enough to be flexible, resulting in a flexible supercapacitor device. The substrate may include (e.g., be formed from) one or more of the following materials: polyimide (e.g., poly(4,4'-oxydiphenylene-pyromellitimide), also known as polyimide), polyetherimide (PEI), poly(methyl methacrylate) (PMMA) (e.g., spray-coated PMMA), polyurethane (PU), polyester, vinyl polymer, carbonized polymer, photoresist polymer, alkyd, urea-formaldehyde.

[0290] These substrate materials can be utilized as carbon sources that are converted to carbon foam using the dual laser process described above. The generation of carbon foam in this manner can be achieved by irradiating a polyimide substrate (for example) with radiation, e.g., laser radiation. This produces carbon foam that is indirectly chemically fixed to the substrate via an intermediate layer of amorphous non-graphene material that is directly attached to the substrate (see earlier herein), resulting in a robust structure. Thus, the electrodes are generated in situ by using a portion of the substrate as a carbon source, i.e., as a reagent to generate the carbon foam. The structure can be robust and flexible at the same time. Flexible devices are advantageous in many ways. Flexible devices can be advantageously packaged, e.g., by rolling up the device. Flexible devices can also be attached to the surface of curved structures, for example.

[0291] The substrate may be substantially planar. The substrate may be a film, e.g., a thin film. The substrate may have a thickness greater than 5 μm. The substrate may have a thickness less than 120 μm. The substrate may have a thickness between 5 μm and 120 μm. The thickness of the substrate may be substantially uniform across the entire surface of the substrate. The substrate may be flexible. The substrate may be pliable.

[0292] The substrate may be a polyimide tape (eg, a polyimide tape) having a first surface and a second surface.

[0293] The electrodes may be mass balanced to optimize the operating voltage window.

[0294] A supercapacitor can be considered as two capacitors connected in series. To maximize the capacitance of a supercapacitor, the capacitance of the two constituent capacitors should be equal. This can be manipulated by adjusting the surface area of ​​the individual electrodes, thus compensating for other factors that contribute to the capacitance, such as the nature of the solvated ions. This process of adjusting the individual electrodes is called mass balancing. Mass balancing of the electrodes has the advantage that it can maximize the capacitance of the superconductor device and can extend the life of the supercapacitor.

[0295] In a second aspect, there is provided a method of manufacturing a symmetric supercapacitor device according to the first aspect, comprising the steps of: An electrode is formed on the substrate; An electrolyte precursor comprising charge carriers and a hydrogel is applied to the electrodes; A method in which an electrolyte is formed from the precursor, causing the electrodes to be embedded in the electrolyte in the active area.

[0296] Carbon foam electrodes can be made by converting a portion of a substrate into carbon foam (if the substrate is or contains a carbon source), or by using chemical or physical deposition techniques such as physical vapor deposition (PVD), chemical vapor deposition (CVD), molecular beam epitaxy (MBE), sputtering, laser induced growth, pulsed laser deposition, cathodic arc deposition, spin coating, dip coating, or sol-gel techniques. In this way, the electrodes are produced in situ on the substrate.

[0297] The electrolyte precursor may be prepared by preparing an aqueous solution of the charge carriers and mixing the aqueous solution with the hydrogel. The electrodes may be formed using laser radiation.

[0298] When preparing the electrolyte precursor, it should be noted that precipitation or crystallization of salts in the electrolyte is undesirable. Precipitation of salts or any solids from the electrolyte can lead to cracking of the device, other defects in the device, or defects in the performance of the device. This places an upper limit on the concentration of the salt solution. It may be advantageous to avoid the use of supersaturated salt solutions. The exact upper concentration limit may depend on the details of the chemicals present. For sodium perchlorate, the inventors have found that a concentration of 5M produces an electrolyte that avoids precipitation or crystallization of salts and also, in combination with other features, gives a supercapacitor device with an operating window that exceeds that expected from consideration of the individual components. The electrolyte may include a salt solution with a concentration greater than 4M. The electrolyte may include a salt solution with a concentration greater than 3M, or greater than 2M, or greater than 1M, or greater than 0.5M.

[0299] At higher concentrations, the salt was observed to readily precipitate from the electrolyte gel, too quickly for a viable device. This precipitation could be caused by water evaporation. Water loss through hydrolysis could be another cause. In any case, we found that concentrations of sodium perchlorate up to 16.5M could be used to form electrolyte gels, but precipitation problems were observed at all concentrations above 10M.

[0300] When preparing hydrogel electrolytes, high molar solutions of salts may be used.

[0301] A less concentrated salt solution is generally advantageous for cost reasons.

[0302] The carbon foam layer may be between 10 μm and 100 μm thick, which promotes flexibility of the device, which may be rolled up to become more compact.

[0303] A gap of between 100 and 1000 μm can separate the electrodes from one another. The capacitance of the device depends on the gap between the electrodes, and therefore adjusting this gap affects the amount of charge that can be stored.

[0304] The operating window of the device may be greater than 1.5V, or greater than 2V, or greater than 2.5V.

[0305] An optional preferred feature of any one aspect of the system may be a feature of any other aspect of the system.

[0306] Appendix 1: Description of drawings Please refer to the following drawings: FIG. 59 presents a positive carbon foam cyclic voltammogram measured at 25 mV / sec. FIG. 60 shows a negative carbon foam cyclic voltammogram measured at 25 mV / sec. Figure 61 shows the 0.5 mA / cm for the positive voltage window. 2 The galvanostatic charge-discharge (GCD) curves of the carbon foam measured at 1000 s are presented. Figure 62 shows the 0.5 mA / cm for the negative voltage window. 2 The galvanostatic charge-discharge (GCD) curves of the carbon foam measured at 1000 s are presented. Figure 63 presents carbon foam galvanostatic charge-discharge (GCD) data obtained from five two-electrode devices. FIG. 64 presents carbon foam cyclic voltammograms recorded from five different two-electrode devices at high (left) and low (right) scan rates. FIG. 65 presents carbon foam cyclic voltammogram data for five additional systems that differ by the nature of the hydrogel electrolyte: (a) 3 M NaClO4 and PVA, (b) 1 M NaClO4 and PVA, (c) 2.5 M NaNO3 and PVA, (d) 3 M Mg(ClO4)2 and PVA, and (e) 5 M NaClO4 and PVP.

[0307] Appendix 1 Detailed Description Two-electrode supercapacitor As shown in FIG. 26, an exemplary carbon foam supercapacitor device according to this aspect has interdigitated carbon foam electrodes. To recap, a polyimide substrate, in this example constructed of carbon foam, supports the supercapacitor electrodes arranged in an interdigitated comb geometry to form an interdigitated electrode structure. Silver current collectors run down each side of the device which helps to electrically unify each opposing electrode. The non-substrate side of the interdigitated electrode structure is encapsulated with a hydrogel. A polyimide lid can be added to contain the hydrogel or the device can be otherwise packaged in a suitable manner.

[0308] As explained above, the carbon foam electrode may be formed on a polyimide substrate. Carbon foam is created on a suitable substrate, which is the substrate that provides the carbon source, in this example a polyimide substrate, by exposing the substrate to a laser beam. The carbon foam thus produced grows from the substrate and is indirectly adhered to the substrate. The substrate and the carbon foam electrode thus formed in situ form one body.

[0309] The carbon foam electrodes were produced using an infrared CO2 laser under ambient conditions. The substrate was a commercially available polyimide film with a nominal thickness of 127 microns. One example has 11 parallel strips of carbon foam for each electrode. This number can obviously be varied. The carbon foam strips for the positive electrode are offset from the carbon foam strips for the second electrode, thus forming an interdigitated structure.

[0310] The electrode dimensions are as shown in Table 6: [Table 6]

[0311] 3-electrode device In addition to the two-electrode supercapacitor device, a three-electrode test device was also fabricated that further included a reference electrode. The three-electrode device comprises a working electrode, a counter electrode, and an Ag / AgCl reference electrode. Each of the working and counter electrodes is made from carbon foam, which is produced in this particular embodiment by dual laser illumination of a polyimide substrate, as previously described. This device is used to determine the voltage range over which the NaClO4 hydrogel electrolyte is stable. The three-electrode device was left to stabilize for at least one hour after fabrication before any measurements were performed.

[0312] Preparation of hydrogel electrolyte Each of the disclosed two-electrode and three-electrode devices is based on a 5M solution of sodium perchlorate, the electrolyte being prepared in the manner described herein. A 5M solution of sodium perchlorate was prepared by dissolving sodium perchlorate (98% purity from Sigma-Aldrich) in deionized water (amount used: 3.061 g NaClO4 in 5 ml deionized H2O). The sodium perchlorate solution was then stirred with a magnetic stirrer on a hot plate at 120°C while adding polyvinyl alcohol (PVA, 99% hydrolyzed, Sigma-Aldrich). For every 10 mL of solution, 1.5 g of PVA was dissolved. The mixture of sodium perchlorate solution and PVA was removed from the hot plate and allowed to cool. The mixture thereby forms a white opaque gel-like solution. The gel solution is then heated to 120°C until it liquefies and becomes transparent. It is then deposited on a graphene electrode. After being deposited on the electrode surface, the liquefied hydrogel electrolyte material solidifies in about 5 minutes at room temperature. The amount of electrolyte deposited on the electrode depends on the surface area to be covered. For the test devices, 150 μL of electrolyte was deposited.

[0313] Experimental results from a three-electrode device The performance that can be obtained from a supercapacitor is ultimately limited by the stability of the electrolyte.

[0314] To test the stability of the electrolyte in this system, several experiments were carried out using the three-electrode device described herein. Differential pulse voltammetry (DPV) was first used to select a voltage window that was then investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) measurements.

[0315] i Cyclic voltammetry To determine the stability of the electrolyte, cyclic voltammetric measurements were performed. In a standard three-electrode measurement, the potential between the working and reference electrodes was swept at a constant rate from the open circuit potential (OCP; nominally 0 V) ​​to a predefined upper limit before being swept again. During this time, the current response at the working electrode was monitored.

[0316] The results of these measurements are shown in Figures 59 and 60. Figure 59 shows the results when the voltage was scanned in the positive direction from the OCP.

[0317] The top set of results shows four voltammograms with maximum potentials of 1 V, 1.2 V, 1.3 V, and 1.4 V. The bottom set of results includes an additional voltammogram with a maximum potential of 1.6 V. As the upper voltage limit is increased beyond 1.2 V, the shape of the cyclic voltammograms becomes less "square-like." The increasingly pronounced tail as the end scan voltage increases indicates electrolyte degradation, likely due to water electrolysis. These voltammograms show that the electrolyte is stable up to +1.2 V.

[0318] Figure 60 shows a similar set of results, but taken for negative voltages. These data suggest that the electrolyte is stable down to -1.4V.

[0319] Taken together, the data in Figures 59 and 60 give an operating window for the device of 2.6 V, which is significantly higher than would be expected from using an aqueous electrolyte.

[0320] ii Galvanostatic charge-discharge (GCD) data Galvanostatic charge-discharge (GCD) measurements were performed to determine the coulombic efficiency from the charge and discharge times. In these measurements, a current is applied between the counter and working electrodes and the voltage response of the working electrode (relative to a reference electrode) is measured. The coulombic efficiency was determined by the 2×10 -5 A(0.5mA / cm 2 The GCD curves measured using a discharge current of 1.2 V are shown in FIG. 61 for positive voltages. The plateau in the curve above 1.2 V indicates electrolyte degradation. The GCD curves for selected negative voltage windows are shown in FIG.

[0321] A significant plateau is seen in the voltage window up to -1.6V and -1.8V, indicating electrolyte degradation. The voltage window of -1.4V has a triangular GCD curve, indicating stability.

[0322] The results of the cyclic voltammetry measurements and the galvanostatic charge / discharge measurements in the three-electrode system are summarized in the table below.

[0323] The first table, Table 7, summarizes the average coulombic efficiency, areal discharge capacitance, and discharge energy data for the positive voltage window. [Table 7]

[0324] The second table, Table 8, summarizes the average coulombic efficiency, areal discharge capacitance, and discharge energy data for the negative voltage window. [Table 8]

[0325] In these summary tables, the coulombic efficiency is the ratio of stored energy to delivered energy measured in the second GCD cycle, in mF / cm 2 The areal capacitance in units of is calculated by the formula:

number

[0326] The GCD curves show that +1.2V and -1.4V are the realistic positive and negative voltage limits.

[0327] These values ​​of voltage limit and areal capacity allow the mass balance to be calculated according to the following formula:

number

[0328] Experimental Results from Two-Electrode Devices-Supercapacitor Performance 0.25mA / cm 2 ~30mA / cm 2 Galvanostatic charge-discharge (GCD) data was collected for two-electrode supercapacitor devices for applied current densities ranging from 0.01 V / s to 5 V / s. FIG. 63 plots the GCD results obtained from five different devices (CH1-CH5). A voltage window of 2.6 V is utilized to collect these data. Greater electrolyte stability is observed at higher current densities. Further performance data for the two-electrode supercapacitor is presented in FIG. 64, which shows cyclic voltammograms recorded from five different devices (Devices #1-#5) according to the present implementations at scan rates ranging from 0.01 V / s to 5 V / s.

[0329] The cyclic voltammograms in the right column were recorded at low scan rates (0.01 V / s, 0.025 V / s, 0.05 V / s, 0.075 V / s, 0.1 V / s, 0.25 V / s, and 0.5 V / s), and the cyclic voltammograms in the left column were recorded at high scan rates (0.75 V / s, 1 V / s, 2 V / s, 3 V / s, 4 V / s, and 5 V / s). The trend shown in these data is in greater electrolyte stability at higher scan rates. In each set of cyclic voltammograms shown in Figure 64, the faster scan voltage results in a greater difference in the current response between increasing and decreasing voltages.

[0330] In addition to the above disclosed devices, devices were constructed in a similar manner but using hydrogel electrolytes containing (a) 3 M NaClO4 and PVA, (b) 1 M NaClO4 and PVA, (c) 2.5 M NaNO3 and PVA, (d) 3 M Mg(ClO4)2 and PVA, and (e) 5 M NaClO4 and PVP.

[0331] Cyclic voltametric measurements on these additional devices are shown in Figure 6. For each electrolyte, cyclic voltammograms were performed between 0V~0.7V, 0V~0.8V, 0V~0.9V, 0V~1.0V, 0V~1.2V, 0V~1.3V, and 0V~1.4V. Similarly, for each electrolyte, cyclic voltammograms were performed between 0V~-0.7V, 0V~-0.8V, 0V~-0.9V, 0V~-1.0V, 0V~-1.2V, 0V~-1.3V, and 0V~-1.4V. These data are shown in Figure 6.

[0332] The data show that in each device, the electrolyte is stable down to limits of -1.4 V and +1.1 V, and +1.2 V for (d) 3 M Mg(ClO4)2 and PVA, and (e) 5 M NaClO4 and PVP, respectively.

[0333] Further variations and modifications may be made within the scope of the present disclosure.

[0334] Appendix 1 Concepts 1. A symmetric supercapacitor device, comprising: two electrodes, each electrode comprising a carbon foam material; and a hydrogel electrolyte encapsulating the electrodes in an active area. 2. A symmetric supercapacitor device as described in concept 1, wherein the hydrogel electrolyte comprises a mixture of hydrogel and salt. 3. A symmetric supercapacitor device according to concept 1 or concept 2, comprising ionic charge carriers. 4. A symmetric supercapacitor device as described in concept 3, wherein the ionic charge carriers are hydrated. 5. A symmetric supercapacitor device according to any one of the preceding concepts, wherein the electrodes comprise carbon foam. 6. A symmetric supercapacitor device according to any one of the preceding concepts, wherein the electrodes comprise a carbon foam material. 7. A symmetric supercapacitor device as described in any one of Concepts 1, 5, and 6, wherein the carbon foam material is formed on a substrate. 8. A symmetric supercapacitor device as described in concept 7, wherein the substrate is a polyimide substrate. 9. A symmetric supercapacitor device according to concept 7 or concept 8, wherein the substrate forms the substrate of the device. 10. A symmetric supercapacitor device according to any one of the preceding concepts, wherein the symmetric supercapacitor device is flexible. 11. A method for producing a symmetric supercapacitor device according to any one of concepts 1 to 10, comprising: An electrode is formed on the substrate; An electrolyte precursor comprising charge carriers and a hydrogel is applied to the electrodes; A method in which an electrolyte is formed from the precursor, causing the electrodes to be embedded in the electrolyte in the active area. 12. A method of making a symmetric supercapacitor device as described in concept 11, wherein the electrolyte precursor is prepared by preparing an aqueous solution of charge carriers and mixing the aqueous solution with a hydrogel. 13. A method for producing a symmetric supercapacitor device according to concept 11 or concept 12, wherein the electrodes are formed in situ. 14. A method of making a symmetric supercapacitor device according to any one of concepts 11-13, wherein electrodes are formed by irradiating the substrate with laser radiation.

[0335] Appendix 2: Gii-Cap+Hydrogel In this Appendix 2 section, we illustrate the effectiveness of Gii carbon foam as an ideal substrate onto which pseudocapacitive materials can be deposited, resulting in significantly enhanced capacitance compared to Gii carbon foam as a single electrode material. For context, these carbon foam-only devices exhibit full-cell specific capacitances in the 0.25-0.4 mF / cm2 region.

[0336] Sample preparation A7 size Gii-Cap was electrodeposited to cast a layer of pseudocapacitive material on it. Both v4 and v5 designs are suitable for electrodeposition and yield similar performance. The results of the v4 sample are detailed in this document.

[0337] A sheet containing six Gii-Cap devices (two rows, three columns) was first cut in half to obtain two three-device half-sheets. The two half-sheets were mounted in a home-made fixture and placed in a MiniPlant3 electrodeposition tank. The samples were first deposited with MnOx, washed with deionized water, and subsequently deposited with FexOy. After FexOy deposition, they were rinsed again and dried in air at 40 °C for at least 2 h.

[0338] The deposition details are as follows: The manganese oxide precursor solution contained a mixture of manganese acetate tetrahydrate (40 mM) and a surfactant (Tween 20, 0.1 wt%). The deposition was performed by galvanostatic pulses. The on-time was 0.5 s and the off-time was 2 s. The on-current applied was 744 mA (19.14 mA / cm2 based on the nominal geometric area of ​​the electrode). The off-current was 0 mA, i.e., open circuit. MnOx was deposited for a total of 390 cycles (3.7 C / cm2 per electrode). The FexOy precursor solution consisted of 40 mM Fe-TEA complex (TEA is triethanolamine). The FexOy precursor solution contained FeCl3, TEA, NaOH. The deposition was also performed by galvanostatic pulses. The on-time was 1 s and the off-time was 2 s. The on-current was 233 mA (6 mA / cm2) and the off-current was set to 0 mA. The deposition was carried out for 1,000 cycles, resulting in 6 C / cm2 per electrode.

[0339] After deposition was completed and the samples were dried, the samples were singulated into individual devices. A quasi-reference electrode (RE) containing screen-printed Ag / AgCl ink (used to monitor individual electrode potentials during testing) was fixed along one of the edges of the device outside the active area. An electrolyte was then applied to the active area of ​​the device and extended onto the RE. The electrolyte used was an aqueous hydrogel containing NaClO4 as the salt and PVA (polyvinyl alcohol) as the gelling agent. A stock batch of hydrogel contains 199.5 g NaClO4 monohydrate, 256.9 ml deionized water, and 42.4 g PVA. The mixture is solid at room temperature and becomes liquid at temperatures close to the boiling point of water. To dispense the hydrogel, the hydrogel was heated to 94°C to liquefy it. Liquid electrolyte was dispensed by pipetting onto the active area and the RE (typically 3-4 ml per device). The hydrogel on the sample was then allowed to cool and resolidify after approximately 10 minutes. After solidification, excessive electrolyte evaporation was prevented by applying a polyimide film over the device. Once the lid was applied, the device was ready for testing.

[0340] Electrochemical Test Parameters Samples were electrochemically tested using a Biological VMP-3 potentiostat / galvanostat. Samples underwent initial performance characterization, followed by 500 charge-discharge cycles (conditioning protocol), and completed with a final characterization. The nominal values ​​reported are those obtained during the second characterization step. The conditioning protocol was applied to give the samples more stable and consistent performance.

[0341] During testing, the voltage was controlled at the cell level (absolute difference between positive and negative electrodes) with a minimum of 0 V and a maximum of 2 V. The potential difference between each electrode and a common RE was also measured, allowing the calculation of individual electrode performance metrics.

[0342] The two characterization steps are known as the Ragone test. The two characterization steps were identical and consisted of: a) Cyclic voltammetry (CV). Three scan rates were used: 50, 100, and 250 mV / s. Five cycles were applied for each scan rate. b) Galvanostatic charge-discharge (GCD). Seven current densities were tested: 1, 2.5, 5, 7.5, 10, 20, and 30 mA / cm2 (based on a total device geometric area of ​​12.96 cm2). Five cycles were performed at each current density. c) Electrochemical impedance spectroscopy (EIS). The voltage is controlled using a DC applied voltage of 1 V and an AC signal of 10 mV. Measurements are made in the range of 1 MHz to 10 mHz. The conditioning step was accomplished by performing 500 GCD cycles at 10 mA / cm2. Nominal capacitance values ​​were calculated from the GCD after conditioning at 5 mA / cm2. ESR (equivalent series resistance) was calculated from the voltage drop at the beginning of the discharge half cycle across the GCD. The reported ESR values ​​are also from the final GCD at 5 mA / cm2. ESR can also be calculated from the Nyquist plot obtained from EIS. The results obtained are almost identical.

[0343] Results and Conclusions A total of 48 devices average was considered. Samples from batches 3258 and 3259 were used. Typical CV curves are shown in Figure 66. The whole-cell response (left panel) shows a quasi-rectangular shape, indicating that the storage mechanism is not purely capacitive. This is expected since both MnOx and FexOy are redox-active materials. Most of the capacitance of the device is concentrated at cell voltages above 0.5 V, as seen by the small envelope of the whole-cell curve in the region 0-0.5 V. An explanation for this smaller capacitance at low cell voltages can be seen in the half-cell curve shown in the right panel of Figure 66. From this graph, it can be seen that MnOx acts as the positive electrode, while FexOy is the negative electrode. MnOx is a nearly ideal pseudocapacitive material, as shown by the rectangular shape of most of its CV (great trace).

[0344] On the other hand, the FexOy electrode shows a more asymmetric response with respect to potential. Most of its capacitance is concentrated at potentials below 0 V vs. Ag / AgCl. At potentials greater than 0 V vs. Ag / AgCl, FexOy displays almost no capacitance, as seen by the small envelope of the blue trace at these potentials. This asymmetric FexOy response therefore explains the smaller capacitance at low voltages obtained for all cells.

[0345] Figure 66 shows post-conditioning CV curves from sample 3258-1#4 obtained at 100 mV / sec. The left panel shows the whole-cell CV, while the right panel displays the half-cell curve obtained during the whole-cell measurement.

[0346] Capacitance calculations were performed using the GCD curves since they provide more accurate values. A typical GCD curve after conditioning is shown in Figure 67, where both full-cell and half-cell measurements are displayed. The device shows good capacitance response with a quasi-triangular curve. The full cell exhibits linear discharge from the maximum voltage to about 0.5V, indicating the near ideal capacitive behavior enabled by the pseudocapacitance of MnOx and FexOy. As can be seen in the CV curves, FexOy shows an asymmetric capacitance vs. potential relationship, which explains the faster discharge at cell voltages below 0.5V.

[0347] Figure 67 shows the post-conditioning GCD curves from sample 3258-1#4 obtained at 5 mA / cm2. The full-cell and corresponding half-cell responses are shown in the top, middle, and bottom lines, respectively.

[0348] In addition to the different pseudocapacitive behavior with respect to potential, MnOx and FexOy electrodes also show different levels of capacitance. Although both electrodes occupy the same geometric area in the device, the MnOx electrode experiences a much smaller electrochemical window in the device (see the difference between the maximum and minimum electrode potentials in Figures 66 and 67). The reason for the smaller MnOx window (0.65 ± 0.06 V) is its larger specific capacitance compared to FexOy (1.35 ± 0.06 V window). In the devices evaluated in this study, the MnOx capacitance after conditioning reached 246.8 ± 36.0 mF / cm2, while the capacitance of the FexOy electrode was 171.4 ± 38.4 mF / cm2. Thus, these Gii-Cap+ devices are symmetrical in terms of electrode dimensions, but asymmetrical in terms of electrode composition and potential division.

[0349] Because the whole cell is effectively two capacitors in series (formed by the double layer between the electrode and electrolyte counterions), the total cell capacitance will be lower than that of a single electrode. The average total cell capacitance after conditioning was 52.5 ± 9.4 mF / cm2. At the same current density used to report the nominal capacitance (64.8 mA at the cell level, 5 mA / cm2), the ESR calculated from the voltage drop at the start of discharge was 0.85 ± 0.12 Ω.

[0350] EIS measurements further confirm the good capacitive response of these devices, as seen in Figure 68. From the Nyquist plot, it is possible to estimate the ESR by identifying the point where the curve crosses the y-axis. For the sample shown in Figure 68, the ESR calculated from EIS was 0.78 Ω, in good agreement with the 0.73 Ω calculated from GCD for the same sample. The Bode plot provides information on the behavior of the device at various frequencies. For example, at high frequencies, from 100 to 10,000 Hz, the device essentially acts like a resistor, with a phase angle of 0°. As the frequency decreases, the phase angle increases, indicating a larger capacitive contribution (an ideal capacitor has a phase angle of -90°). Once the phase angle is above the 45° mark, the device is considered to be mostly capacitive in nature. Therefore, the time at which a 45° phase shift occurs can be considered as the characteristic time constant of the device. For the samples in this study, the average time constant was 4.48 ± 1.18 seconds. This time constant can be understood as the cycle time threshold for a valid capacitive response. At cycle times below the time constant the device does not operate satisfactorily.

[0351] Figure 68 shows post-conditioning Nyquist (left) and Bode (right) plots from sample 3258-1#4 obtained from potentiostatic EIS at DC (whole cell) of 1 V. The inset in the left panel shows a zoomed-in view of the high frequency response.

[0352] Considering that devices utilizing Gii as the sole electrode material exhibit specific capacitances of 0.25-0.4 mF / cm2, the addition of pseudocapacitive materials increased the energy storage capacity of these Gii caps by more than 100-fold. Furthermore, the addition of these metal oxides does not significantly increase the ESR of these devices, preserving their usefulness in high power applications. The electrodeposition process is controllable, allowing for the fabrication of cells with less deposited material and therefore less total capacitance, if desired. The resulting devices are asymmetric in nature, with MnOx as the primary positive electrode and FexOy as the negative counterpart.

[0353] Appendix 3 GiiCap Ion Gel Objective: To demonstrate the specific capacitance and electrochemically stable window (ESW) of an electrolyte formulation containing the room temperature molten salt 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4) and fumed silica, known as ion gel, in conjunction with a GiiCap® A7 device in a "low" humidity and "air-free" argon atmosphere environment.

[0354] Test conditions: All electrochemical tests were performed under a “three-electrode” setup in which regular interdigitated A7 devices were fabricated with a 1:2 “working” and “counter” electrode area ratio, with the “working” electrode containing screen-printed AgCl ink to monitor the individual electrode potentials during testing.

[0355] Electrolyte ion gels were prepared and stored in an air-free environment.

[0356] Prior to application onto the A7 devices for testing, the ion gel was heated to 90°C and then dispensed onto the A7 devices by "doctor blading" a thin, consistent layer. The electrolyte was allowed to cool before the devices were ready for testing and connection. For air-free devices, testing was performed in the same air-free environment where the electrolyte was stored and dispensed and the device was connected to the following electrochemical test equipment: Biological VMP-3 potentiostat.

[0357] For the low humidity environment, the devices were transferred to a humidity-controlled chamber set at 20% relative humidity, sealed, and connected to the instrument.

[0358] For each humidity level, a range of maximum electrode potentials (Emax) in volts (V) close to the nominal literature values ​​for neat electrolytes were tested. These were: Correct: 2.0, 1.9, 1.8, 1.7, 1.6, 1.5 Negative: -2.0, -1.9, -1.8, -1.7, -1.6

[0359] For each humidity and electrode potential combination, N=8 samples were made from scratch.

[0360] Electrochemical test parameters: A standard protocol was used and the test window was 0.0-Emax V vs. OCV. OCV is Quantified as 0.25 V vs AgCl Qref. The electrochemical testing was divided into three stages: a) Ragone characterization, b) long-term (LT) cycling, and c) Ragone characterization (post).

[0361] Ragone characterization both before and after LT cycling included the following: OCV, 1 h, at 100 and 1000 mV / s for 5 cycles each; cyclic voltammetry (CV), 5 and 10 mA / cm for 10 cycles each. 2 Galvanostatic charge-discharge (GCD) at 10 MHz and potentioelectrical impedance spectroscopy (PEIS) at 0.01 Hz. LT cycling included the following: CV of 750 mV / sec for 5000 cycles;

[0362] The electrochemical stability was assessed by visual post-mortem analysis of electrode damage and electrolyte discoloration, and by evaluation of the change in coulombic efficiency over the LT cycling period.The device performance was determined from the specific capacitance by GCD after 5000 LT cycles.

[0363] Conclusion: ESW was determined by plotting the coulombic efficiency of LT CV cycles versus cycle number. If the coulombic efficiency was consistent through 5000 cycles, the cycling Emax was determined to be stable for a given environmental condition. From this analysis, it was found that in air with 20% relative humidity, the Ion Gel-A7 device was stable at negative and positive electrode potentials of -1.6 and +1.6 V, respectively. In an airless environment, the negative and positive ESW were determined to be -1.8 V and +1.7 V, respectively.

[0364] In terms of performance evaluation, in the positive window, the 20% relative humidity and airless devices had 2.11 and 1.60 mF / cm 2 The negative window specific capacitances in the 20% and air-free environments were 1.55 and 2.11 mF / cm 2 It was.

[0365] Figures 69, 70 and 71 are the relevant results.

[0366] Figures 72, 73 and 74 are further related results.

[0367] Appendix 4. Gii-Sens assay feasibility proposal for 3 months the purpose: Provide a proof of feasibility project with key reagents for the Gii-Sens3D carbon foam assay system.

[0368] Phase 1: Surface immobilization Goal: Maximize surface immobilization of mAb (2). Evaluate the most convenient surface chemistry to immobilize mAb onto the surface. Deliverable: Maximum surface coverage and data supporting the selected procedure.

[0369] Phase 3: Target analyte detection range and LOD Objectives: Electrochemical immunoassay procedures and results. Establish the electrochemical immunoassay steps (incubation time, concentration, volume) and establish the parameters that result in the most sensitive analytical assay.

[0370] Deliverables: Data supporting the performance of the electroanalytical immunoassay.

[0371] Experimental Section Solution Composition surface chemistry 10 mM pyrene butyrate in DMF 4mM EDC / 10mM SulfoNHS PBS 0.1M pH7.2 reading 1 mM K3Fe(CN)6 + 1 mM K4Fe(CN)6 in 0.02M KCl 0.02M PBS

[0372] Sensor change procedure Apply 10 µL of PyrBuOOH onto the sensor surface, which was incubated for 2 h in a humid chamber before allowing for spontaneous solvent evaporation. 15 μL EDC / NHS for 30 min 10 μL of A1 or C1 mAb in PBS for 1 hour

[0373] Electrochemical techniques Electrochemical Impedance Applied voltage = 0V Amplitude=0.01VRMS Frequency range: -5000~0.1Hz

[0374] Assay procedure Direct assay: label-free: see Figures 75 and 76. Direct Assays: Label-Free and Reagent-Free See Figures 77 and 78.

[0375] Calibration Plot Number of replicates per point, n=5 (minimum) different disposable sensors (single reading, sensors are deployed) Each calibration plot contains data acquired on subsequent days and by different operators (inter- and intra-assay variability)

[0376] Phase 1: Surface Chemistry The surface chemistry chosen was EDC / NHS conjugation of Pyr-COOH modified graphene and capture mAbs (A1 and C1) according to the scheme in Figure 79 showing the surface immobilization reaction schematic.

[0377] The concentrations of surface-immobilized mAbs (A1 and C1) were screened using electrochemical impedance spectroscopy (see Experimental Section). See Figure 80 (mAb A1 immobilization on Gii-Sens® surface. Intercalated normalized signal) and Figure 81 (mAb C1 immobilization on Gii-Sens® surface. Intercalated normalized signal).

[0378] Both A1 and C1 showed a logical surface coverage trend. Based on the normalized curves, A1 showed a slightly larger surface coverage. The optimal coverage range was screened to be 15-250 μg / mL. That concentration range was estimated to be sufficient to provide the best performance of the sensor.

[0379] Phase 3: Assays and target analyte discovery A more detailed evaluation of the assay possibilities and benefits of using Gii-Sens® as a sensing electrochemical platform was always carried out in a label-free assay format. In parallel, it was also explored a reagent-free format, where the solution used for both incubation and readout signal was simply a buffer solution, as described in the experimental section. The dynamic range of the assay was also explored at higher concentrations to see the possibility of extending its concentration range.

[0380] Due to the interesting results obtained during the above mentioned investigations and the general time constraints, the sensitivity of the assay was explored down to 10 pg / mL with the aim to explore a higher concentration range up to 1000 ng / mL.

[0381] Free Assay Discovery Label-free assays as described above did not require a secondary antibody but consisted of assays that used a specific electrochemical readout solution, which during this investigation was also used as the carrier solution, thus eliminating the need for washing steps or other assay complications.

[0382] The first concentration range explored was from 10 ng / mL to 10 pg / mL for both A1 and C1 modified sensors. See Figure 82 showing label-free dose response curves for A1 (top) and C1 (bottom) sensors to varying concentrations of N1 antigen. Surface coatings greater than 60 μg / mL and assay incubation times of 6 minutes for all cases.

[0383] Both A1 and C1 responded similarly and achieved good preliminary dose-response curve characteristics for the concentration range studied. To further explore ways to improve the performance of the assay, the overall concentration range was divided and different sensitivity ranges were explored using the same data obtained.

[0384] Label-free and Reagent-free Assay Discovery Label-free assays as described above consist of assays that do not require a secondary antibody. In the reagent-free case, all incubations and measurements are performed in a buffer solution that also serves as a carrier solution, thus eliminating the need for an electrochemical readout solution, further eliminating the need for additional washing steps.

[0385] The first concentration range explored was from 10 ng / mL to 10 pg / mL for both A1 and C1 modified sensors. See Figure 83 showing label-free and reagent-free dose response curves for A1 (top) and C1 (bottom) sensors to varying concentrations of N1 antigen. Surface coatings greater than 60 μg / mL and assay incubation times of 6 minutes for all cases.

[0386] Both A1 and C1 responded similarly and achieved good preliminary dose-response curve characteristics for the concentration range studied.

[0387] Appendix 5. Sensor implementations in which receptors are bound to 3D carbon foam materials via linkers [Background technology] A sensor is an analytical device that detects changes or reactions and responds to some type of input from the environment. In recent years, the use of sensors has increased due to their advantages such as high specificity and sensitivity, fast and reliable results, easy handling, point-of-care diagnostics, etc. Due to these advantages, sensors have been introduced into diverse technology fields such as chemical and medical diagnostics, environmental impact analysis, food industry, marine sector, etc.

[0388] Various forms of graphene and its derivatives have been utilized in the production and development of sensors, especially biosensors. The electrochemical, physical, and chemical properties of graphene make it an attractive material for these applications. However, traditional graphene (e.g., 2D graphene) is difficult to handle during practical applications due to its ultra-thin structure and flexibility, which makes it easily curl, crease, and corrugate. This significantly reduces the analytical performance of the sensor, especially in terms of its sensitivity. To date, many strategies and techniques have been implemented to fabricate different types of graphene (e.g., different morphologies, different surface properties, different functionalized derivatives such as graphene quantum dots, graphene oxide, or reduced graphene oxide), which cause differences in sensing performance between sensors.

[0389] EAObaje, G. Cummins, H. Schulze, S. Mahmood, MPY Desmulliez and TTBachmann, Journal of Interdisciplinary Nanomedicine, 2016;0(0), doi:10.1002 / jin2.16 investigate the electrochemical performance of the newly fabricated sensors in relation to the functionality of the underlying composite material and evaluate the selection of carbon and dielectric pastes by characterizing properties such as surface roughness, wetting, and sensitivity of non-specific DNA binding.

[0390] LHHess, A. Lyuleeva, BMBlaschke, M. Sachsenhauser, M. Seifert, and JAGarrido, ACS Appl. Materials & Interfaces, 2014, 6, 9705-9710 describes a platform for biosensing applications based on polymer-modified CVD-grown graphene transistors.

[0391] C. Fenzl, P. Nayak, T. Hirsch, OS Wolfbeis, HN Alshareef, and AJ Baeumner, ACS Sensors, 2017, 2, 616-620, describe laser scribed graphene (LSG) electrodes as highly sensitive and reliable biosensor transducers in serum analysis.

[0392] S. Singhal, A.K. Srivastava, S. Dhakate, A.M. Biradar and Rajesh, RSC Advances, 2015, 5, 74994-75003, describe an electroactive graphene multi-walled carbon nanotube hybrid supported inhibition immunosensor for detection of human cardiac troponin-I.

[0393] Despite all the prior art, there is a continuing need to improve the sensing activity of these graphene-based sensors. Furthermore, it remains desirable to improve the sensitivity of these sensors without compromising at least one of their other aspects, such as their robustness, stability, durability, ease of functionalization, and / or ease of manufacture.

[0394] [Summary of the Invention] In a first aspect, there is provided a sensor comprising: (i) a carbon foam electrode; (ii) a linker; and (iii) a receptor, the receptor being coupled to the carbon foam electrode via the linker, the carbon foam electrode being fabricated, at least in part, by a method as defined in any of Features A-K above.

[0395] In a second aspect, there is provided a method of producing a sensor according to the first aspect, comprising the sequential steps of: (i) providing a carbon foam electrode according to the first aspect; (ii) treating the carbon foam electrode with a linker; and (iii) treating the linker-modified carbon foam electrode obtained in step (ii) with a receptor.

[0396] In a third aspect, there is provided a method of sensing a target comprising, in sequence, (i) providing a sensor according to the first aspect, (ii) contacting the sensor with a sample containing or suspected of containing the target, (iii) measuring a response of the sensor, and optionally (iv) correlating the response with the level of the target in the sample.

[0397] Carbon foam materials typically have a folded structure that gives the carbon foam a porous morphology with a high specific surface area. Without wishing to be bound by any theory, it is believed that the analytical performance of the sensor is influenced by the morphology and the accessible surface area of ​​the carbon foam. The 3D structure leads to an increase in the available surface area, allowing linkers and receptors such as enzymes, proteins, nucleic acids, and antibodies to be efficiently bound to the carbon foam, thus improving the sensor performance in terms of sensitivity.

[0398] Additionally, it is also desirable to construct a sensor with a very thick carbon foam layer. Preferably, the thickness of the carbon foam layer is greater than 50 μm. Because carbon foam can be porous, this thick carbon foam layer is expected to provide a larger surface area, which is advantageous for improving analytical performance, especially sensing properties, compared to other conventional graphene-based sensors.

[0399] Linker In the context of this aspect, carbon foam is modified with a linker as part of the process to form the required sensor. The carbon foams described above (e.g., thick porous carbon foams with folded structures) provide an improved substrate for modification since increased surface area is available for interaction with the linker, leading to improved sensor sensitivity.

[0400] The modified carbon foam is then treated with a receptor to obtain a sensor. Thus, the linker serves as an intermediate between the carbon foam and the receptor. At least a portion of the linker can be disposed (e.g., dispersed) within the carbon foam. The entire linker can be disposed (e.g., dispersed) within the carbon foam.

[0401] The linker may be selected from a nanoparticle, a polymer, a polymer brush, a ligand, an organic compound containing one or more functional groups, a molecule covalently or non-covalently bonded to the carbon foam, or a mixture thereof. Typically, the linker is selected from a polymer, (e.g., a (meth)acrylate polymer), an organic compound containing one or more functional groups, a carbodiimide, a diazonium compound, or a mixture thereof.

[0402] Typically, the organic compounds described above include one or more functional groups independently selected from oxygen, nitrogen, sulfur, halide, hydroxyl, carbonyl, carboxyl, amine, amino, amide, hydrophilic polymer, or mixtures thereof, optionally in combination with linear, branched, or cyclic alkyl, alkylenyl, alkynyl, aryl residue, acryl, acyl, acyloxy, alkoxy, alkyleneoxy, or mixtures thereof. In the same embodiment, the optional structure may be a C1-C20 linear, branched, or cyclic alkyl, alkylenyl, alkynyl, aryl residue, acryl, acyl, acyloxy, alkoxy, alkyleneoxy, or mixtures thereof. Further in the same embodiment, optionally, the organic compound having the above-mentioned functional groups further comprises one or more cyclic moieties, optionally containing one or more heteroatoms, at least one of which is directly or indirectly bonded to at least one of the functional groups, or the linker is an ester or salt derivative of such an organic compound, or a compound that reacts with the required 3D carbon foam to release such an organic compound. Typically, the linker is selected from the organic compounds as described above in this paragraph.

[0403] Typically, the linker is selected from 1-pyrenebutyric acid, N-hydroxysuccinimide (NHS), pyrene-1-carboxylic acid succinimidyl ester, 1-aminopyrene, N-(1-pyrene)maleimide, or a mixture thereof.

[0404] The linker may be covalently or non-covalently bound to the carbon foam. For example, a diazonium compound (e.g., a diazonium salt) may be covalently bound to the carbon foam. In the case of non-covalent binding, the linker may be bound to the carbon foam by at least one of the following: π-π interactions, ionic bonds, hydrogen bonds, hydrophobic or hydrophilic effects, electrostatic interactions, polymer wrapping, adsorption, grafting (e.g., photografting). For example, a linker comprising one or more cyclic moieties as described above (e.g., 1-pyrenebutyric acid, N-hydroxysuccinimide (NHS), pyrene-1-carboxylic acid succinimidyl ester, 1-aminopyrene, N-(1-pyrene)maleimide, or mixtures thereof) may be bound to the carbon foam by π-π interactions.

[0405] In the context of this feature, the receptor is attached to the carbon foam via a linker. Thus, the receptor is indirectly attached. When at least a portion of the linker, or preferably the entire linker, is disposed (e.g., dispersed) within the carbon foam, at least a portion or the entire receptor is also disposed (e.g., dispersed) within the carbon foam.

[0406] "Receptor" in this specification is meant to include any molecule that can respond to a target substance (i.e., target) presented in the sample to be analyzed. The sample can be a biological sample, a chemical sample, an optical sample, a physical sample, or a mechanical sample, typically a biological sample. Thus, the target is meant to include, but is not limited to, biological materials, chemical substances or mixtures, optical objects, physical or mechanical items, and the like, typically biological materials. The term "respond" can include, but is not limited to, biological and / or chemical and / or optical and / or physical and / or mechanical interactions, typically biological and / or chemical interactions. These typical interactions can include, but are not limited to, binding between the receptor and the target, or hybridization, or hydrophobic effects.

[0407] Thus, the receptor may include, but is not limited to, one of electrochemical receptors, chemical receptors, bioreceptors, optical receptors, physical or mechanical receptors. The receptor may be selected from, but is not limited to, crown ethers, ligands, catalysts, boric acid, carbohydrates, aptamers, proteins, enzymes, antibodies, antigens, microorganisms, nucleic acids, fatty acids, fatty acid esters, molecularly imprinted polymers, metal organic frameworks, polypeptides or oligopeptides capable of forming ligand bonds, cells, organelles, or other cellular components, or mixtures thereof.

[0408] Typically, the receptor is a biological receptor (i.e., the sensor is a biosensor). Typically, the receptor is selected from an aptamer, a protein, an enzyme, an antibody, an antigen, a microorganism, a nucleic acid, a polypeptide or oligopeptide, a cell, an organelle, or other cellular component capable of forming a ligand bond, or a mixture thereof. More typically, the receptor is selected from a protein (e.g., an immune protein, a non-immune protein, an immunoglobulin-binding protein, a sugar-binding protein), a nucleic acid, an antibody, an enzyme (e.g., an oxidoreductase enzyme (preferably a glucose oxidase, an alcohol oxidase, or a lactate oxidase enzyme), a dehydrogenase enzyme), or a mixture thereof. Typically, the receptor is selected from immunoglobulin A (IgA), glucose dehydrogenase, streptavidin, or a mixture thereof.

[0409] Typically, the target is a biomaterial. The biomaterial may include, but is not limited to, deoxyribonucleic acid (DNA), ribonucleic acid (RNA), peptides, proteins, protein complexes, nucleic acids, antibodies, antigens, lipids, fatty acids, fatty acid esters, vitamins, microorganisms, micelles, cells, organelles, or other cellular components, viruses, enzymes, or mixtures thereof. Typically, the biomaterial is selected from deoxyribonucleic acid (DNA), ribonucleic acid (RNA), peptides, proteins, nucleic acids, antibodies, antigens, enzymes, or mixtures thereof. More typically, the biomaterial is selected from proteins, nucleic acids, antibodies, enzymes, or mixtures thereof. Furthermore, it is to be understood that in the context of this feature, both the native receptor and the biomaterial can be naturally occurring or synthetically produced.

[0410] The receptor can be bound to the linker. The receptor can be physically, biologically, and / or chemically bound to the linker. Typically, the receptor is chemically bound to the linker. As used herein, chemical bonds may include, but are not limited to, covalent bonds, non-covalent bonds (e.g., ionic bonds), metal bonds, hydrogen bonds, chelate bonds, and non-covalent interactions such as van der Waals forces, π-π interactions, hydrophobic or hydrophilic effects, and electrostatic interactions. Typically, the receptor (e.g., bioreceptor) is covalently bound to the linker. Typically, the receptor (e.g., bioreceptor) is bound (e.g., covalently) to one or more functional groups (e.g., functional groups of an organic compound as described above) contained in the linker. For example, the bioreceptor can be covalently bound to a carboxyl group, or an amino or amine, or an amide group (e.g., 1-pyrenebutyric acid, N-hydroxysuccinimide (NHS), pyrene-1-carboxylic acid succinimidyl ester, 1-aminopyrene, N-(1-pyrene)maleimide) of the linker.

[0411] Sensors The sensor according to this aspect typically comprises a layer of carbon foam, which can be produced by the dual laser processing method disclosed above. Typically, the carbon foam has a layer thickness of more than 50 μm, preferably more than 100 μm, more preferably more than 200 μm, even more preferably more than 300 μm. Typically, at least a portion of the linker or the entire linker is disposed (e.g., dispersed) in the carbon foam. Optionally, at least a portion of the receptor or the entire receptor is also disposed (e.g., dispersed) in the carbon foam (i.e., at least a portion of the linker, or preferably the entire linker is disposed (e.g., dispersed) in the carbon foam). Typically, at least a portion of the linker, and optionally at least a portion of the receptor, is disposed (e.g., dispersed) at a depth below the surface of the carbon foam (e.g., carbon foam layer) that is more than 1% of the total depth of the carbon foam, preferably more than 5% of the total depth, more preferably more than 10%, even more preferably more than 15%, even more preferably more than 20%. Typically, at least a portion of the linker, and optionally at least a portion of the receptor, is disposed (e.g., dispersed) at a depth greater than 1 μm, preferably greater than 5 μm, more preferably greater than 10 μm, even more preferably greater than 15 μm, and most preferably greater than 20 μm below the surface of the carbon foam. The entire linker and optionally the entire receptor can be disposed (e.g., dispersed) at a depth greater than 1% of the total depth of the carbon foam below the surface of the carbon foam (e.g., the carbon foam layer). The carbon foam layer can have a thickness in any of the ranges described above (e.g., at least greater than 50 μm). As used herein, "dispersed" means that the linker (and optionally receptor) molecules at least partially disposed within the carbon foam are distributed throughout the carbon foam to form multiple distinct domains other than a single cluster. The domains can be uniformly and / or continuously distributed within the carbon foam (e.g., distributed as a uniform and / or continuous layer). Without wishing to be bound by any theory, it is believed that displacement of the linker (and optionally the receptor) leads to improved functionalization of the carbon foam, thereby increasing the sensing activity (i.e., sensitivity) of the sensor.

[0412] Additionally, optionally, neither the linker nor the receptor is disposed (e.g., dispersed) throughout the depth of the carbon foam (e.g., the carbon foam layer), in other words, the core of the carbon foam remains unmodified with either the linker or the receptor.

[0413] The linker can be selected from 1-pyrenebutyric acid, N-hydroxysuccinimide (NHS), pyrene-1-carboxylic acid succinimidyl ester, 1-aminopyrene, N-(1-pyrene)maleimide, or a mixture thereof, and the receptor can be selected from immunoglobulin A (IgA), glucose dehydrogenase, streptavidin, or a mixture thereof.

[0414] The sensor can also include a substrate. In the first method for obtaining carbon foam, if the carbon source is provided on or adjacent to a substrate, the final sensor may include said substrate as a component. In the second method, where the use of a substrate is required, the final sensor may also include said substrate as a component. Once obtained by either method, the carbon foam may optionally be adhered to the substrate in the sensor. The substrate thus included in the sensor may have characteristics according to one of the characteristics described above for the substrate used to generate the carbon foam and / or one of the possible combinations of those characteristics. Alternatively, the sensor does not have to include a substrate. In other words, the carbon foam may be produced adhered to a substrate, but it may be removed from the substrate as part of the preparation for subsequent modification.

[0415] Typically, the sensor according to this feature is a chemical, physical or mechanical, biological, or optical sensor, preferably a biosensor (i.e., where the receptor is a biological receptor). Typically, the sensor (e.g., a biosensor) is in the form of an electrode or electrode device. The sensor (e.g., a biosensor) may include a multi-electrode platform, for example, a three-electrode platform including a counter electrode (CE), a working electrode (WE), and a reference electrode (E or RE). The electrode (e.g., WE) may be composed of the modified carbon foam of this feature (i.e., carbon foam modified with a receptor via a linker). The other electrodes (e.g., CE and / or RE) may also be carbon foam based, preferably carbon foam based, more preferably the same carbon foam based without any modification. All electrodes may have the same or different dimensions.

[0416] The sensor (e.g., biosensor) may be provided as a product in which the sensor is included in packaging, and the product preferably includes instructions for use. Typically, the packaging includes a primary packaging in which the sensor is included. The sensor can be provided on an adapter that is included in the primary packaging. Suitable examples of the primary packaging are protective covers, pockets, folders, envelopes, boxes, containers, cartons, cases, etc. Optionally, the packaging further includes secondary packaging. Such secondary packaging is typically packaging that holds the sensor or sensors together. Suitable examples for secondary packaging are plastic cartons, cardboard cartons, blister packs, boxes (e.g., cardboard or plastic boxes), cases, containers, cardboard or plastic crates, trays, wrapped bundles with or without one or more air pockets, etc. Optionally, the packaging may further include tertiary packaging, which may be selected from boxes, cases, cartons, containers, etc. Preferably, at least one of the above packagings can protect the sensor from light (e.g., direct sunlight), moisture, physical and / or chemical damage, and contaminants. The instructions may provide detailed information of steps of using the sensor according to the third aspect of the feature. The instructions may be provided in the printed form of a label, booklet, pamphlet, or leaflet. The instructions may also be printed on the product packaging.

[0417] Sensor Manufacturing In a second aspect, there is provided a method of manufacturing a sensor according to the first aspect, comprising the steps of: (i) providing a carbon foam; (ii) treating the carbon foam with a linker; and (iii) treating the linker-modified carbon foam with a receptor.

[0418] The method can include a step of manufacturing the carbon foam before providing and treating it with the linker. Thus, the carbon foam is produced by one of the laser treatment methods disclosed herein, typically the first method or the second method, more typically the first method. The carbon foam so produced can be adhered to a substrate, attached to a substrate, or provided on a substrate. Typically, the carbon foam may be removed from the substrate before the treatment of the linker in step (ii). In other words, the carbon foam of step (i) is provided without a substrate. Alternatively, the carbon foam does not need to be removed (e.g., the carbon foam remains adhered to the substrate). In other words, the carbon foam of step (i) is provided with a substrate.

[0419] The carbon foam can be incubated with the linker. The incubation can preferably be carried out in a buffer solution. Additionally or optionally, the modification with the linker can require at least one of the following conditions: light (ultraviolet, visible, or infrared radiation), or heat. After incubation, the linker-modified carbon foam can be washed.

[0420] The linker-modified carbon foam can be incubated with a receptor. After incubation, the sensor so obtained can be washed before use. After washing, the sensor can be passivated. Passivation is understood to block remaining active sites that are not functionalized by a receptor.

[0421] A receptor used to treat the linker-modified carbon foam in step (iii).

[0422] The sensor may be an electrode device including an electrode or a multi-electrode platform. Thus, the manufacturing process described above may be applicable to the manufacture of an electrode. If the sensor is an electrode device including a multi-electrode platform, the manufacturing process described above is applicable to the production of the working electrode (WE), and the method further includes the following additional steps of producing a counter electrode (CE) and a reference electrode (E or RE).

[0423] Using the Sensor In a third aspect, there is provided a method of using a sensor comprising, in sequence, the steps of: (i) providing a sensor according to the first aspect; (ii) contacting the sensor with a sample containing or suspected of containing a target; (iii) measuring a response of the sensor; and (iv) optionally correlating the response with the level of the target in the sample.

[0424] The target may be a target as disclosed herein, typically a biological material as disclosed herein. The sample may be a sample as disclosed herein, typically a biological sample as disclosed herein.

[0425] Prior to use, the sensor (e.g., biosensor) can be suitably stored at ambient conditions (e.g., room temperature of about 20° C. and 1 atmosphere pressure). Typically, the sensor is stored under dry conditions. After use, the sensor can be suitably disposed (i.e., the sensor is a disposable sensor).

[0426] The sensor can be immersed in the sample. The sample may contain phosphate buffered saline (PBS). The concentration of the target in the sample may be at least 1 ppm. The equilibration time can be at least 0.5 minutes, or at least 1 minute, or at least 10 minutes, or at least 30 minutes, typically no more than 2 hours, or no more than 1 hour, or no more than 40 minutes. After contacting the sample, the sensor can be washed before the response is measured. The sensor can be washed by rinsing with PBS. After washing, the sensor can be dried (e.g., by gas flow or by air drying).

[0427] The response can be measured by differential pulse voltammograms and / or impedance spectroscopy. The measured response can be further correlated to the level of the target in the sample. The method can include steps (i), (ii), and (iii) above, and can additionally include: (iv) contacting the sensor with one or more samples containing known levels of the target (i.e., control samples); (v) measuring the response of the sensor to the one or more control samples; (vi) comparing the response to the sample containing or suspected of containing the target with the response to the one or more control samples; and (vii) correlating the response to the sample containing or suspected of containing the target with the level of the target in the sample.

[0428] Appendix 5 Concepts 1. A sensor comprising: (i) a carbon foam; (ii) a linker; and (iii) a receptor, wherein the receptor is attached to the carbon foam via the linker. 2. The sensor of concept 1, wherein the carbon foam is obtained by a method of concentrating infrared radiation at at least one location within a carbon source, thereby producing carbon foam within said at least one location, and wherein said infrared radiation is provided by a laser beam that is an infrared laser beam. 3. The sensor of claim 2, wherein concentrating the infrared radiation includes diffracting the infrared radiation to form an interference pattern, each of whose fringes is within a location within the carbon source. 4. The sensor of concept 2 or concept 3, wherein at least one location is moved laterally within the carbon source and / or at least one location is moved within the depth of the carbon source. 5. The sensor of any one of concepts 2-4, wherein the infrared radiation directly irradiates the carbon source or the infrared radiation passes through a substrate before irradiating the carbon source, and the carbon source is provided on or adjacent to a surface of the substrate. 6. The sensor of any one of concepts 2-5, wherein the carbon source is additionally irradiated with additional radiation, and this additional irradiation is performed prior to, simultaneously with, or subsequent to the step of concentrating the infrared radiation at at least one location within the carbon source. 7. The sensor of claim 6, wherein additional radiation is rastered onto the surface of the carbon source. 8. The sensor of concept 6 or concept 7, wherein additional radiation either directly irradiates the carbon source or passes through the substrate as described in concept 5 before irradiating the carbon source. 9. A sensor according to any one of the preceding concepts, wherein at least a portion of the linker is disposed, preferably dispersed, within the carbon foam, and optionally at least a portion of the receptor is disposed dispersed within the carbon foam. 10. The sensor according to any one of concepts 2 to 9, wherein the carbon foam has a layer thickness of more than 50 μm, preferably more than 100 μm, more preferably more than 200 μm, even more preferably more than 300 μm. 11. The sensor of concept 1, wherein the carbon foam is obtained by a process comprising providing a carbon source on or adjacent to a surface of a substrate, and exposing at least a portion of the carbon source and / or at least a portion of the substrate comprising a carbon-containing material to a laser beam, thereby converting at least a portion of the carbon source to carbon foam. 12. The sensor of concept 5, 8, or 11, wherein the substrate comprises one or more of silicon, silicon dioxide, gallium nitride, gallium arsenide, zinc oxide, or alternatively one or more polymers, or alternatively one or more metals selected from aluminum, copper, gold or other metals, or oxides, nitrides, or arsenides of such metals. 13. A sensor according to any one of the preceding concepts, wherein the carbon foam comprises an atomic percentage of oxygen of less than 3%, preferably less than 1.5%, and / or an atomic percentage of nitrogen of less than 3%. 14. The sensor of any one of the preceding concepts, wherein the linker is selected from a nanoparticle, a polymer, a polymer brush, a ligand, an organic compound comprising one or more functional groups, a molecule covalently or non-covalently bound to the carbon foam, or a mixture thereof. 15. The sensor of concept 14, wherein the linker is preferably selected from a (meth)acrylate polymer, an organic compound containing one or more functional groups, a carbodiimide, a diazonium compound, or a mixture thereof. 16. The sensor of concept 15, wherein the one or more functional groups are independently selected from oxygen, nitrogen, sulfur, halide, hydroxyl, carbonyl, carboxyl, amine, amino, amide, hydrophilic polymer, or mixtures thereof, optionally in combination with linear, branched, or cyclic alkyl, alkylenyl, alkynyl, aryl residues, acryl, acyl, acyloxy, alkoxy, alkyleneoxy, or mixtures thereof. 17. The sensor of concept 16, wherein the organic compound further comprises one or more cyclic moieties, optionally including one or more heteroatoms, and at least one of the cyclic moieties is directly or indirectly bonded to at least one of the functional groups, or the linker is a derivative that is an ester or salt of the organic compound, or a compound that reacts with the carbon foam to release the organic compound. 18. The sensor of concept 17, wherein the linker is selected from 1-pyrenebutyric acid, N-hydroxysuccinimide (NHS), pyrene-1-carboxylic acid succinimidyl ester, 1-aminopyrene, N-(1-pyrene)maleimide, or a mixture thereof. 19. The sensor of concept 17 or concept 18, wherein the linker is attached to the carbon foam by π-π interactions. 20. The sensor according to any one of the preceding concepts, wherein the receptor is one of an electrochemical receptor, a chemical receptor, a bioreceptor, an optical receptor, a physical or mechanical receptor, preferably a bioreceptor. 21. The sensor according to claim 20, wherein the receptor is selected from a crown ether, a catalyst, a boric acid, a concept, a ligand, an aptamer, a protein, an enzyme, an antibody, an antigen, a microorganism, a nucleic acid, a fatty acid, a fatty acid ester, a molecularly imprinted polymer, a metal-organic framework, a polypeptide or oligopeptide capable of forming a ligand bond, a cell, an organelle or other cellular component, or a mixture thereof, preferably selected from a protein, a nucleic acid, an antibody, an enzyme, or a mixture thereof. 22. The sensor of concept 21, wherein the receptor is selected from immunoglobulin A (IgA), glucose dehydrogenase, streptavidin, or a mixture thereof. 23. The sensor according to any one of the preceding concepts, wherein the receptor is physically, biologically and / or chemically bound to the linker, preferably chemically bound, more preferably covalently bound. 24. A method for producing a sensor according to any one of the preceding concepts, comprising the steps of (i) providing a carbon foam according to any one of concepts 1 to 13, 19, (ii) treating the carbon foam with a linker according to any one of concepts 1, 14 to 19, 23, and (iii) treating the linker-modified carbon foam obtained in step (ii) with a receptor according to any one of concepts 1, 20 to 23. 25. A method for sensing a target, comprising the steps of: (i) providing a sensor according to any one of concepts 1 to 23; (ii) contacting the sensor with a sample containing or suspected of containing the target; (iii) measuring a response of the sensor; and, optionally, (iv) correlating the response with the level of the target in the sample.

[0429] It is also noted that the sensor described in this Appendix 5 may be the Gii-Sens carbon foam sensor described earlier in this specification.

[0430] Appendix 6 Benchmark experiment conditions 1 mM ferric potassium / ferrocyanide in 0.1 M strontium nitrate with a minimum of 5 randomly selected replicates. Cyclic voltammetry at scan rates of 25 mV / s and 200 mV / s was performed as a comparison technique. Various features were investigated and conclusions were drawn to assess the differences in the performance of the electrode materials.

[0431] Electrochemical impedance spectroscopy was performed at equilibrium potential with an amplitude of 5 mV and frequencies ranging from 0.1 to 100 kHz. A silver / silver chloride reference electrode was used either built into the sensor or externally.

[0432] GiiSens Carbon Foam vs. Traditional Graphene Electrode Materials The GiiSens carbon foam sensor was evaluated and compared with other commercially available graphene-based sensors, see Figure 84.

[0433] The resulting reduction and oxidation peak currents recorded show a 25% higher efficiency in terms of current density per geometric area, clearly reflecting the larger available electrochemically exploitable area provided by the GiiSens 3D carbon foam, see FIG.

[0434] From cyclic voltammetry, evaluation of the reduction-oxidation peak separation can be interpreted as a measure of the electronic redox responsiveness of the surface to the voltage scan and its ability to effectively carry out rapid redox reactions. Studies have shown that the reduction-oxidation peak separation remains below 70 mV and does not show an increased separation from 25 mV / s to 200 mV / s.

[0435] Other graphene electrode surfaces exhibited larger voltage separation from reduction to oxidation, demonstrating the apparent detrimental effects associated with less efficient redox reactions and faster scan rates, see FIG.

[0436] The values ​​of the charge transfer resistance at different surfaces show a dramatic improvement for the GiiSens sensor surface, indicating the great potential of GiiSens for implementing impedance-based measurements with high reliability and low background signal interference.

[0437] GiiSens vs. other carbon-based materials Carbon-based electrode materials are very common in electroanalytical applications. Carbon paste electrodes are a common material for screen-printed sensors. They are the most widespread electrode surfaces in practical point-of-care applications due to their manufacturing flexibility and affordability. On the other hand, carbon-based materials are glassy carbon surfaces and have better expected performance but limited availability due to flexible manufacturing and affordability. See Figure 87.

[0438] The performance of GiiSens carbon foam has been shown to match that of pure vitreous carbon material in terms of available electrochemically active area while increasing the available area by 50% over a comparably sized carbon paste electrode, see Figure 88.

[0439] The reduction-oxidation peak separation obtained from cyclic voltammetry shows a high dependency on the slow scan rate, which is due to the poor performance of the carbon paste material and relatively acceptable redox reactions on its surface. The response of GiiSens is superior to that of pure glassy carbon at any scan rate, indicating great potential for combining flexibility of fabrication conditions with excellent performance. See Figure 89.

[0440] Measurements of surface charge transfer resistance highlight that GiiSens holds tremendous potential as an impedance-based sensing surface on vitreous carbon, opening up fields not yet accessible to carbon paste electrode materials.

[0441] GiiSens vs. Screen Printed Gold Screen printed gold sensors host two of the most important properties for making a sensor material feasible in practical electrochemical sensing applications: flexible processing procedures and excellent electrochemical response. Two commercially available examples of screen printed gold were evaluated; see Figure 90. GiiSens carbon foam has also been proven to host these properties while adding affordability.

[0442] The recorded reduction and oxidation peak currents indicate at least a 20% increase in the available electrochemically active area per geometric area unit, see FIG.

[0443] As expected, screen printed gold represents the most responsive electrode surface material of the lots evaluated, but Gii-Sens matches and even improves its performance, especially at fast scan rates. See Figure 92.

[0444] Charge transfer resistance of the electrode surfaces compared to screen printed gold and GiiSens highlights the great potential of the Gii carbon foam material, which in all cases shows lower resistance related values.

[0445] The comparison of GiiSens with screen-printed gold is intended to show a winning comparison in terms of ease of manufacturing and superior performance, while affordability and scalability are crucially beneficial inherent features of the GiiSens sensor.

[0446] conclusion The performance of the GiiSens sensor exceeds other carbon-based or even graphene sensors available on the market. Even screen-printed gold surfaces perform better, removing any shadow of doubt regarding the complete convenience of using the GiiSens surface as the ultimate electrochemical platform for sensing. For the first time, GiiSens represents the best choice for manufacturing and scalable materials for electroanalytical applications, while maintaining the highest performance and ensuring maximum sensitivity and flexibility for implementation in large-scale throughput and point-of-care applications.

[0447] Appendix 7 Optimization of surface immobilization of anti-human procalcitonin (cAb) the purpose: Optimization of surface immobilization of anti-human procalcitonin (cAb) Summary of results Selected surface NHS generation method. Matching with existing standard manufacturing processes · Optimal cAb surface coverage achieved using 100μg / ml cAb. For standard bare Gii-Sens® sensors, the typical %CV is 7%. For all sensors across the experiments shown in this report, the %CV for a 100 μg / ml cAb coating is 10%. Successful detection of 2000 pg / ml Ag in the direct assay format using 100 μg / ml cAb coating. The signal output has a %CV of 10%. Experimental Section Solution Composition surface chemistry NHS qualified Pyren NHS Capture antibody (cAb): Product name: Anti-h PCT 4004 SPTN-5 Antigen (Ag): Product name: Recombinant PCT antigen Echem reading solution 1 mM K3Fe(CN)6 + 1 mM K4Fe(CN)6 in 20 mM KCl cAb immobilization solution Anti-hPCT in 1x PBS (pH 7.2) Antigen (Ag) detection solution 1 mM K3Fe(CN)6 + 1 mM K4Fe(CN)6 + Ag in 20 mM KCl Electrochemical techniques Electrochemical Impedance Applied voltage: OCP Amplitude: 0.01V RMS Frequency range: 100000~0.1Hz Cyclic Voltammetry Scanning speed: 25mV / s Starting potential: -0.3V Upper potential: 0.6 V V lower potential: -0.3 V Assay procedure NHS fixation Prepare 10 mM PyrNHS in DMF Drop-cast 10 μL onto the working electrode of each sensor. Place the sensor inside an airtight box and leave it to incubate for 12-18 hours. Ensure that the PyrNHS / DMF has completely evaporated from the surface. cAb immobilization procedure Place the NHS GiiSens+ sensor on a flat surface. Drop-cast 10 μL of cAb onto the working electrode of each sensor. Place the sensor inside a closed container with a water bath for 2 hours. Remove the sensor and gently rinse the solution with deionized water and then gently dry with a stream of N2 gas. Assay Procedure: Direct Assay 1 - See Figure 93. 1) cAb readout - electrochemical readout solution applied to the sensor surface before taking the EIS measurement. 2) Solution removal - The solution removed from the sensor surface is the electrochemical reading solution. 3) t'1 read - antigen spiked electrochemical read solution applied to the sensor surface before taking the EIS measurement. Approximately 1 min between solution addition and measurement. 4) t'2 reading - EIS measurement is taken. Approximately 6 minutes between solution addition and measurement. 5) t'3 reading - EIS measurement is taken. Approximately 11 minutes between solution addition and measurement. See Appendix for electrochemical readout procedure 1.Characteristics plot Number of replicates per point, n=5 (minimum) different disposable sensors (single reading, sensors are deployed)

[0448] Phase 1: Surface Chemistry The surface chemistry chosen was NHS modified carbon foam followed by conjugation of the cAb via amide bond formation according to the following scheme: See Figure 94: Schematic of the surface immobilization reaction.

[0449] NHS generation on the carbon foam surface was monitored using electrochemical impedance spectroscopy and cyclic voltammetry, see Figure 95: Rct and ΔEp signal responses for NHS functionalization of GiiSens® electrode.

[0450] The increase in Rct and ΔEp relative to the bare electrode confirms the NHS functionalization of the carbon foam electrode.

[0451] Electrochemical impedance spectroscopy was used to screen cAb concentrations ranging from 50 to 800 μg / ml. See Figure 96: cAb immobilization on GiiSens® electrodes.

[0452] A logical increase in Rct with cAb concentration is observed for immobilization on NHS modified sensors. The optimal coverage was estimated to be 100 μg / ml cAb on the NHS electrode, a concentration that was estimated to provide the best performance of the sensor without wasting material with only minor gains. At this concentration, an excellent level of reproducibility (%CV 3%) is observed.

[0453] Phase 2: Electrochemical signal The resulting electrochemical signal was evaluated for the direct assay, which means that there is no use of a secondary antibody to assist in antigen detection.

[0454] For the direct assay investigation, an antigen concentration of 2000 pg / ml was selected. According to the results of the first phase of this report, the surface antibody coating was fixed at 100 μg / ml. The Ag-Ab incubation time was selected as a preliminary assay parameter for investigation. See Figure 97: Signal response from 2000 pg / ml in the direct assay format with 100 μg / ml cAb surface coating.

[0455] The 100 μg / ml cAb again shows a good level of reproducibility (%CV 8%). The distinction between the average cAb Rct is clear, giving a clear quantifiable signal output (ΔRct). The ΔRct signal output also shows an acceptable level of reproducibility with %CV ≥ 10% at each read time. The stability of the output signal between 1, 6, and 11 m indicates that no additional Ab-Ag interactions occur after the first measurement. The 5 min time gap between measurements is due to the length of time taken for the EIS measurement. The assay incubation time is optimal at 1 min for the 2000 pg / ml Ag sample. [Table 9] [Table 10]

[0456] Appendix 8 Comprehensive list of features and optional features This Appendix 8 is a consolidated list of features and optional features. It should be noted that any one or more of the following features A-R may each be combined with any one or more of the other compatible features A-R, and any one or more of the optional features. Group 1: Sub-surface carbon foam Feature A: Carbon foam fabricated in the sub-surface region of carbon precursor material Feature B: Carbon foam created in encapsulated regions of carbon precursor material Feature C: A carbon foam fabricated in a region of a carbon precursor material, the region being substantially free of gas escape paths. Feature D: Amorphous non-graphene material adhered to substrate Group 2: Dual Laser Processing Feature E: Carbon foam created by laser ablation of sub-surface carbon foam regions Feature F: Non-graphene carbon foams produced by laser ablation of subsurface carbon foam regions Feature G: Dual laser Feature H: Electrical contacts located in carbon foam created by laser ablation of sub-surface carbon foam regions Feature I: Printing of electrical contacts on polyimide film and then creating exposed carbon foam Feature J: Toll Raceways Made with Carbon Foam Feature K: Application of primary and secondary lasers in different manufacturing facilities Group 3: Products Feature L1: Biosensor Feature L2: Scalable, low-cost fabrication of carbon foam biosensors using screen printing technology Feature L3: Addition of functional groups to biosensors in different manufacturing facilities Feature L4: Addition of functional groups to biosensors as part of the biosensor generation process Feature L5: Biosensor manufacturing using PPC: Post-print conversion Feature M1: Energy storage device: Supercapacitor Feature M2: Carbon foam supercapacitor details Feature M3: Carbon Foam Supercapacitor: Common Collector Feature M4: Carbon foam supercapacitor: PPC manufacturing process Feature M5: Carbon Foam Pseudocapacitor: Metal Oxide Variant Feature M6: Carbon Foam Supercapacitors: Using Ion Gel in Low Humidity Environments Feature N1: Conductor Feature N2: Combined sensor and supercapacitor Feature N3: Combined supercapacitor and battery Feature N4: Smart Label Feature N5: Combined Supercapacitor and Antenna Feature N6: Combined energy scavenger + supercapacitor. Feature O1: 3D Carbon Foam Construction: Gii-Thru for Gii-Cap Features O2: 3D carbon foam construction: Gii-Thru stackable Gii-Cap / Gii-Cap+ Feature O3: 3D Carbon Foam Construction: Gii-Thru for Gii-Sens: HISLOC Features O4 3D Carbon Foam Construction: Gii-Thru for Gii-Sens: HISLOC Manufacturing Process Group 4: Others Feature P: Scalable Manufacturing of Carbon Foam: Gii3 Feature Q: Various other carbon foam applications Feature R: Non-graphene carbon foam

[0457] Feature A: Carbon foam fabricated in the sub-surface region of carbon precursor material 1. A method of producing a carbon foam material, comprising irradiating a sub-surface region of a carbon precursor material, wherein parameters of a laser beam are selected to create carbon foam in the sub-surface region.

[0458] 1. A laser-induced carbon foam material made by a laser beam configured to irradiate a sub-surface region of a carbon precursor material, the parameters of the laser beam being selected to produce carbon foam in the sub-surface region.

[0459] A device comprising a laser-induced carbon foam material produced by irradiating a sub-surface region of a carbon precursor material, wherein parameters of a laser beam are selected to produce carbon foam in the sub-surface region.

[0460] Feature B: Carbon foam created in encapsulated regions of carbon precursor material 1. A method of producing a carbon foam material, comprising irradiating an encapsulated region of a carbon precursor material, wherein parameters of a laser beam are selected to create carbon foam in the encapsulated region.

[0461] 1. A laser-induced carbon foam material made by a laser beam configured to irradiate an encapsulated region of a carbon precursor material, wherein parameters of the laser beam are selected to produce carbon foam in the encapsulated region.

[0462] A device comprising a laser-induced carbon foam material produced by irradiating an encapsulated region of a carbon precursor material, wherein parameters of a laser beam are selected to produce carbon foam in the encapsulated region.

[0463] Feature C: A carbon foam fabricated in a region of a carbon precursor material, the region being substantially free of gas escape paths. 1. A method for producing a carbon foam material, comprising irradiating an encapsulated sub-surface region of a carbon precursor material, wherein parameters of a laser beam are selected to create carbon foam in that region, and wherein no substantial gas escape path to the surface of the precursor material is created by the laser beam.

[0464] A laser-induced carbon foam material with a laser beam configured to irradiate an encapsulated sub-surface region of a carbon precursor material, where parameters of the laser beam are selected to create carbon foam in that region, and where no substantial gas escape path to the surface of the precursor material is created by the laser beam.

[0465] A device comprising a laser-induced carbon foam material produced by irradiating an encapsulated sub-surface region of a carbon precursor material, wherein parameters of a laser beam are selected to create carbon foam in that region, and wherein no substantial gas escape path to the surface of the precursor material is created by the laser beam.

[0466] Feature D: Amorphous non-graphene material adhered to substrate 1. A method of producing a carbon foam material, the method comprising: irradiating an interior region of a carbon precursor material positioned on a substrate, where laser beam parameters are selected to create carbon foam in the region and to create disordered amorphous non-graphene material between the carbon foam region and the substrate, where the disordered amorphous non-graphene material adheres directly to or otherwise adheres to the substrate.

[0467] 1. A laser organic carbon foam material made by a laser beam configured to irradiate an interior region of a carbon precursor material positioned on a substrate, where parameters of the laser beam are selected to create carbon foam in the region and to create disordered amorphous non-graphene material between the graphene region and the substrate, where the disordered amorphous non-graphene material sticks directly to or otherwise adheres to the substrate.

[0468] 1. A device comprising a laser organic carbon foam material produced by irradiating an interior region of a carbon precursor material positioned on a substrate, wherein parameters of a laser beam are selected to create carbon foam in the region and to create disordered amorphous non-graphene material between the graphene region and the substrate, where the disordered amorphous non-graphene material sticks directly to or otherwise adheres to the substrate.

[0469] Feature E: Carbon foam created by laser ablation of sub-surface carbon foam regions 1. A method of producing graphene material, the method comprising: (a) a laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create carbon foam in the encapsulated or sub-surface region and to create disordered amorphous non-graphene material above the carbon foam; and (b) laser ablation or treatment to remove at least a portion of the disordered amorphous non-graphene material and expose at least a portion of the carbon foam.

[0470] 1. A laser organic carbon foam made by (a) laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create carbon foam in the encapsulated or sub-surface region and create disordered amorphous non-graphene material above the carbon foam, and then (b) laser ablation or processing to remove the disordered amorphous non-graphene material and expose at least a portion of the carbon foam.

[0471] 1. A device comprising: a laser organic carbon foam material produced by (a) laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create carbon foam in the encapsulated or sub-surface region and create disordered amorphous non-graphene material above the carbon foam; and then (b) laser ablation or processing to remove the disordered amorphous non-graphene material and expose at least a portion of the carbon foam.

[0472] Feature F: Non-graphene carbon foams produced by laser ablation of subsurface carbon foam regions 1. A method for producing a non-graphene carbon foam, comprising: (a) a laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create a carbon foam at the encapsulated or sub-surface region of the carbon precursor material and to create a disordered amorphous non-graphene material above the carbon foam; and then (b) laser ablation or treatment to remove the disordered amorphous non-graphene material and expose at least a portion of the underlying carbon foam and convert at least a portion of the underlying carbon foam to non-graphene carbon foam.

[0473] 1. A laser-induced carbon foam comprising: (a) a laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create a carbon foam at the encapsulated or sub-surface region of the carbon precursor material and to create a disordered amorphous non-graphene material above the carbon foam; and then (b) laser ablation or treatment to remove the disordered amorphous non-graphene material and expose at least a portion of the underlying carbon foam and convert at least a portion of the underlying carbon foam to non-graphene carbon foam.

[0474] A device, comprising: (a) a laser beam irradiating an encapsulated or sub-surface region of a carbon precursor material to create a carbon foam at the encapsulated or sub-surface region of the carbon precursor material and to create a disordered amorphous non-graphene material above the carbon foam; and then (b) a step of laser ablation or treatment to remove disordered amorphous non-graphene material and expose at least a portion of the underlying carbon foam, and convert at least a portion of the underlying carbon foam to non-graphene carbon foam.

[0475] Feature G: Dual lasers operating at different frequency bands 1. A method of making a carbon foam material, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material above the carbon foam to expose at least a portion of the carbon foam.

[0476] 1. A laser-induced carbon foam comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam.

[0477] A device, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam.

[0478] Feature H: Electrical contacts located in carbon foam created by laser ablation of sub-surface carbon foam regions 1. A method of making a carbon foam material, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) removing or ablating material overlying the carbon foam using a laser beam operating in a second band to expose at least a portion of the carbon foam; (c) attaching, printing or placing one or more electrical contacts into the carbon foam.

[0479] 1. A laser-induced carbon foam comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) removing or ablating material overlying the carbon foam using a laser beam operating in a second band to expose at least a portion of the carbon foam; (c) attaching, printing or placing one or more electrical contacts onto the carbon foam.

[0480] A device, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) removing or ablating material overlying the carbon foam using a laser beam operating in a second band to expose at least a portion of the carbon foam; (c) attaching, printing or placing one or more electrical contacts onto the carbon foam.

[0481] Feature I: Printing of electrical contacts on polyimide film and then creating exposed carbon foam 1. A method of making a carbon foam material, comprising: (a) screen printing electrical contacts onto or within a carbon precursor material; (b) using a laser beam operating in a first band to irradiate an encapsulated or sub-surface region of the carbon precursor material below the surface of the material to create carbon foam in the encapsulated or sub-surface region, wherein steps (a) and (b) can be performed in the order of (a) followed by (b), or (b) followed by (a); (c) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam to which the electrical contacts are connected.

[0482] 1. A laser-induced carbon foam material comprising: (a) screen printing electrical contacts onto or within a carbon precursor material; (b) using a laser beam operating in a first band to irradiate an encapsulated or sub-surface region of the carbon precursor material below the surface of the material to create carbon foam in the encapsulated or sub-surface region, wherein steps (a) and (b) can be performed in the order of (a) followed by (b), or (b) followed by (a); (c) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam to which an electrical contact is connected.

[0483] A device, comprising: (a) screen printing electrical contacts onto or within a carbon precursor material; (b) using a laser beam operating in a first band to irradiate an encapsulated or sub-surface region of the carbon precursor material below the surface of the material to create carbon foam in the encapsulated or sub-surface region, wherein steps (a) and (b) can be performed in the order of (a) followed by (b), or (b) followed by (a); (c) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam to which an electrical contact is connected.

[0484] Feature J: Toll Raceways Made with Carbon Foam 1. A method of making a carbon foam material, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; The method wherein the carbon foam is at least 50 μm thick or deep.

[0485] 1. A laser-induced carbon foam material comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; The laser-induced carbon foam material, wherein the carbon foam is at least 50 μm thick or deep.

[0486] A device, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; The device, wherein the carbon foam is at least 50 μm thick or deep.

[0487] Feature K: Application of primary and secondary lasers in different manufacturing facilities 1. A method of manufacturing a device, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; The process, wherein step (a) is performed in one manufacturing facility and step (b) is performed in a different facility.

[0488] 1. A laser-induced carbon foam material comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; A laser-induced carbon foam material, wherein step (a) is performed in one manufacturing facility and step (b) is performed in a different facility.

[0489] A device, comprising: (a) irradiating an encapsulated or sub-surface region of a carbon precursor material below a surface of the material using a laser beam operating in a first band to create carbon foam in the encapsulated or sub-surface region; and then (b) using a laser beam operating in a second band to remove or ablate material overlying the carbon foam to expose at least a portion of the carbon foam; A device, wherein step (a) is performed in one manufacturing facility and step (b) is performed in a different facility.

[0490] Feature L1: Biosensor A method of manufacturing a biosensor comprising a sensing electrode comprising a carbon foam made at least in part by the method defined in any of Features A-K above.

[0491] A biosensor comprising a sensing electrode comprising a carbon foam made at least in part by the method defined in any of Features A-K above.

[0492] A point-of-care diagnostic device comprising a biosensor having a sensing electrode comprising a carbon foam made at least in part by the method defined in any of Features A-K above.

[0493] Feature L2: Scalable, low-cost fabrication of carbon foam biosensors using screen printing technology A method of manufacturing a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each electrode comprising, at least in part, a carbon foam made by a method defined in any of Features A-K above, the method comprising: screen printing electrical connection traces onto each electrode; and at least in part covering the electrodes and connection traces with a screen printed dielectric.

[0494] A biosensor including sensor electrodes, such as a working electrode and a counter electrode, each electrode comprising, at least in part, a carbon foam made by the method defined in any of Features A-K above, the biosensor including (i) an electrical connection trace screen printed on each electrode, and (ii) a screen printed dielectric at least partially covering the electrodes and the connection traces.

[0495] Feature L3: Addition of functional groups to biosensors in different manufacturing facilities A method of manufacturing a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each of which comprises carbon foam made at least in part by a method defined in any of Features A-K above, at one manufacturing facility, the method including the further step of adding a functionalizing group to at least the working electrode at a different manufacturing facility.

[0496] A biosensor including sensor electrodes, such as a working electrode and a counter electrode, each electrode comprising carbon foam made at least in part at one manufacturing facility by a method defined in any of Features A-K above, wherein the biosensor includes functionalization groups added to at least the working electrode at a different manufacturing facility.

[0497] Feature L4: Addition of functional groups to biosensors as part of the biosensor generation process A method of manufacturing a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each comprising carbon foam made at least in part by a method defined in any of Features A-K above, at a single manufacturing facility, the method including the further step of adding a functionalizing group to the working electrode at the manufacturing facility.

[0498] A biosensor including sensor electrodes, such as a working electrode and a counter electrode, each electrode comprising carbon foam made at least in part at a single manufacturing facility by a method defined in any of Features A-K above, wherein the biosensor includes functionalization groups added to at least the working electrode at the same manufacturing facility.

[0499] Feature L5: Biosensor manufacturing using PPC: Post-print conversion A method of manufacturing a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each comprising carbon made at least in part by a method defined in any of Features A-K above, the method comprising: (a) screen printing a carbon layer onto a carbon precursor substrate; (b) screen printing an electrical connection trace and a reference electrode; (c) screen printing a dielectric layer onto the carbon layer and the electrical connection traces and the reference electrode; and (d) fabricating a carbon foam sensor electrode using the process defined in any of Features A-K above.

[0500] A biosensor including sensor electrodes, such as a working electrode and a counter electrode, the biosensor including (a) a carbon layer screen printed onto a carbon precursor substrate; (b) screen printed electrical connection paths and a screen printed reference electrode; (c) a dielectric layer screen printed onto the carbon layer and the electrical connection paths and the reference electrode; and then (d) a carbon foam sensor electrode made using a process defined in any of Features A-K above.

[0501] Feature M1: Energy storage device A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, wherein an energy storage electrode comprises, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0502] An energy storage device, such as a supercapacitor or pseudocapacitor, wherein an energy storage electrode comprises, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0503] Feature M2: Screen-printed layers of carbon foam supercapacitors A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, comprising: an energy storage electrode comprising a carbon foam material made, at least in part, by the method defined in any of Features A-K above; The method includes the steps of screen printing electrical connection traces onto at least a portion of each electrode, and at least partially covering the electrodes and the connection traces with a screen printed dielectric layer.

[0504] An energy storage device, such as a supercapacitor or pseudocapacitor, wherein an energy storage electrode comprises, at least in part, a carbon foam material made by the method defined in any of Features A-K above; An energy storage device comprising: a screen printed electrical interconnect wiring formed over at least a portion of each electrode; and a screen printed dielectric layer at least partially covering the electrodes and the interconnect wiring.

[0505] Feature M3: Carbon Foam Supercapacitor: Common Collector A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, wherein an energy storage electrode comprises a carbon foam material made at least in part by the method defined in any of Features A-K above and arranged in an interdigitated pattern; The method includes screen printing an electrical connection trace onto at least a portion of each electrode, the single electrical connection trace connecting to underlying digits extending vertically from either side of the electrical connection trace.

[0506] An energy storage device, such as a supercapacitor or pseudocapacitor, wherein an energy storage electrode comprises, at least in part, a carbon foam material made by the method defined in any of Features A-K above and arranged in an interdigitated pattern; An energy storage device, wherein screen printed electrical connection wiring paths are formed over at least a portion of each electrode, with a single electrical connection wiring path connecting to underlying digits that extend vertically from both sides of the electrical connection wiring path.

[0507] Feature M4: Carbon foam supercapacitor: PPC manufacturing process 1. A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, comprising: The method includes: (a) screen printing an electrical connector onto a substrate; (b) screen printing a carbon layer onto an electrical collector; (c) screen printing a dielectric onto at least a portion of the carbon layer; and (d) fabricating a carbon foam energy storage electrode at least in part by a method defined in any of Features A-K above.

[0508] 1. An energy storage device, such as a supercapacitor or pseudocapacitor, An energy storage device comprising: (a) screen printing an electrical connector on a substrate; (b) screen printing a carbon layer on an electrical collector; (c) screen printing a dielectric on at least a portion of the carbon layer; and (d) fabricating a carbon foam energy storage electrode at least in part by a method defined in any of Features A-K above.

[0509] Feature M5: Carbon Foam Supercapacitor: Metal Oxide Variant A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, comprising: an energy storage electrode comprising a carbon foam material made, at least in part, by the method defined in any of Features A-K above; The method includes applying an electrochemical deposition process of a pseudocapacitive material, such as a metal oxide, to an energy storage electrode.

[0510] 1. An energy storage device, such as a supercapacitor or pseudocapacitor, An energy storage device comprising: (a) an energy storage electrode made of a carbon foam material made at least in part by the method defined in any of Features A-K above; and (b) a pseudocapacitive material, such as a metal oxide, applied to the energy storage electrode.

[0511] Feature M6: Carbon Foam Supercapacitors: Using Ion Gel in Low Humidity Environments A method of manufacturing an energy storage device, such as a supercapacitor or pseudocapacitor, comprising: an energy storage electrode comprising a carbon foam material made, at least in part, by the method defined in any of Features A-K above; The method includes applying an ion gel electrolyte in a low humidity but non-inert environment, wherein the levels of O2 and HO in the environment are measured and controlled to optimize the capacitance of the energy storage device.

[0512] 1. An energy storage device, such as a supercapacitor or pseudocapacitor, 1. An energy storage device comprising: (a) an energy storage electrode comprised at least in part of a carbon foam material made by the method defined in any of Features A-K above; and (b) an ion gel electrolyte applied to a low humidity but non-inert environment, wherein levels of O and HO in the environment are measured and controlled to optimize a capacitance of the energy storage device.

[0513] Feature N1: Conductor A method of manufacturing an electrical conductor, the electrical conductor comprising, at least in part, a carbon foam made by the method defined in any of Features A-K above.

[0514] A conductor comprising, at least in part, a carbon foam made by the method defined in any of Features A-K above.

[0515] Feature N2: Combined sensor and supercapacitor A method of manufacturing a device including both a sensor and an energy storage device such as a supercapacitor, wherein both the sensor and the energy storage device include a carbon foam material made, at least in part, by the method defined in any of Features A-K above.

[0516] A sensor device, such as a biosensor, comprising: (a) a sensing electrode comprising a carbon foam material made at least in part by the method defined in any of Features A-K above; and (b) an energy storage device, such as a supercapacitor, wherein the energy storage device comprises, at least in part, a carbon foam material made at least in part by the method defined in any of Features A-K above.

[0517] A point-of-care diagnostic device comprising: (a) a sensing electrode comprising a carbon foam material made at least in part by the method defined in any of Features A-K above; and (b) an energy storage device, such as a supercapacitor, wherein the energy storage device comprises, at least in part, a carbon foam material made at least in part by the method defined in any of Features A-K above.

[0518] Feature N3: Combined supercapacitor and battery A method of manufacturing an integrated device including a battery and a supercapacitor, wherein the battery provides long term power and the supercapacitor provides short term power at a level higher than the battery, and the supercapacitor comprises, at least in part, a carbon foam material made by a method defined in any of Features A-K above.

[0519] An integrated device including a battery and a supercapacitor, wherein the battery provides long term power and the supercapacitor provides short term power at a level higher than the battery, the supercapacitor comprising, at least in part, a carbon foam material made by a method defined in any of Features A-K above.

[0520] Feature N4: Smart Label A method of manufacturing a smart label, comprising combining or integrating a battery and a supercapacitor, wherein the battery provides long term power and the supercapacitor provides short term power at a higher level than the battery, the supercapacitor comprising a carbon foam material made at least in part by a method defined in any of features A-K above; A method in which a smart label includes electronics, such as sensor electronics powered by a battery and a data transmitter powered by a supercapacitor.

[0521] A smart label comprising a battery and a supercapacitor, the battery providing long term power and the supercapacitor providing short term power at a level higher than that of the battery, the supercapacitor comprising a carbon foam material made at least in part by a method defined in any of features A-K above; A smart label includes electronics, such as sensor electronics powered by a battery and a data transmitter powered by a supercapacitor.

[0522] Feature N5: Combined Supercapacitor and Antenna A method of manufacturing an integrated device comprising an antenna and a supercapacitor, the supercapacitor powering the antenna and comprising, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0523] An integrated device comprising an antenna and a supercapacitor, the supercapacitor powering the antenna and comprising, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0524] Feature N6: Combined energy scavenger + supercapacitor. A method of manufacturing an integrated device, comprising combining or integrating an energy scavenger system and a supercapacitor, the supercapacitor powering an antenna and comprising, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0525] A data logging device comprising an energy scavenger system and a supercapacitor, the supercapacitor powering an antenna and comprising, at least in part, a carbon foam material made by the method defined in any of Features A-K above.

[0526] Feature O1: 3D Carbon Foam Construction: Gii-Thru for Gii-Cap 1. A method of manufacturing an energy storage device, comprising: (i) providing a carbon precursor film; (ii) screen printing a conductive paste or conductive ink layer onto the surface of the carbon precursor film; (iii) screen printing a collector layer onto the screen printed conductive paste or conductive ink layer; (iv) screen printing a dielectric layer onto the collector layer; (v) forming an energy storage electrode comprising a carbon foam material from the carbon precursor film by a method at least in part as defined in any of Features A-K above; A method in which a conductive path is formed from the carbon foam material to the collector layer through a conductive paste or conductive ink layer.

[0527] An energy storage device, such as a supercapacitor, comprising: (i) a carbon precursor film; (ii) a screen printed conductive paste or conductive ink layer on the surface of the carbon precursor film; (iii) a screen printed collector layer over the screen printed conductive paste or conductive ink layer; (iv) a screen printed dielectric layer on the collector layer; (v) an energy storage electrode comprising a carbon foam material made at least in part from a carbon precursor film by the method defined in any of Features A-K above, wherein a conductive path is formed from the carbon foam material to the collector layer through a conductive paste or conductive ink layer.

[0528] Features O2: 3D carbon foam construction: Gii-Thru stackable Gii-Cap / Gii-Cap+ 1. A method of manufacturing an energy storage device, comprising: (i) providing a carbon precursor film; (ii) screen printing a conductive paste or conductive ink layer onto the s...

Claims

1. 1. A method of making a carbon foam material, comprising: (a) using a first laser beam to irradiate an encapsulated sub-surface region of a carbon precursor material below a surface of the carbon precursor material to create carbon foam at the encapsulated sub-surface region; and (b) using a second laser beam to remove or ablate material overlying the carbon foam to expose or modify at least a portion of the carbon foam to produce a resultant carbon foam material.

2. The method of claim 1 , wherein the first laser beam operates in a first band and the second laser beam operates in a second band.

3. parameters of the first laser beam irradiating the encapsulated sub-surface region include one or more of intensity, wavelength, pulse frequency, pulse duration, pulse profile, scan speed, focal length, and heat generated at the encapsulated sub-surface region; and Varying the laser parameters of the first laser beam alters the properties of the carbon foam material, allowing the resulting carbon foam material to be produced with properties optimized for different applications. The method of claim 1.

4. 4. The method of claim 3, wherein varying the laser parameters of the first laser beam alters one or more of the following properties or parameters of the resulting carbon foam material: type of carbon nanostructures present, size of defects, distribution of defects, extent of defects, type of defects, size of the Raman D peak, relative size of the Raman D and 2D peaks, thickness or depth, flexibility, adhesion, porosity, electrical conductivity, capacitance, absorption of organic solvents and aqueous solutions, hydrophilicity, EMI shielding, electrode quality, wettability, contact angle, and anti-fouling.

5. 10. The method of claim 1, wherein no substantial gas escape path to the surface of the precursor material is created by the first laser beam.

6. The method of claim 1 , wherein the first laser beam has a wavelength that has substantially zero or very low absorbance by the carbon precursor material.

7. The method of claim 1 , wherein the encapsulated sub-surface region has a thickness of between 10 μm and 200 μm.

8. The method of claim 1 , wherein the carbon precursor material is made substantially of a thermoset material.

9. The method of claim 1 , wherein the carbon precursor material is made of a substantially non-thermoplastic material.

10. 10. The method of claim 1, wherein the carbon precursor material carbon source comprises or is formed from one or more polymers.

11. the carbon precursor material is positioned on or adjacent to a substrate; and the surface of the carbon precursor material is transformed by the laser beam into a disordered amorphous non-graphene material that sticks or bonds to the substrate, thus indirectly attaching a 3D carbon material foam to the substrate; The method of claim 1.

12. 10. The method of claim 1, wherein the surface of the carbon precursor material is converted by the first laser beam to a disordered amorphous non-graphene material.

13. the parameters of the second laser beam include one or more of intensity, wavelength, pulse frequency, pulse duration, pulse profile, scan speed, focal length, and heat generated in the sub-surface region or encapsulated region; Varying the second laser parameters alters the properties of the resulting carbon foam material, allowing the resulting carbon foam material to be produced with properties optimized for different applications; and Varying the laser parameters of the second laser beam alters one or more of the following properties or parameters of the resulting carbon foam material: type of carbon nanostructures present, size of defects, distribution of defects, extent of defects, type of defects, size of Raman D and 2D peaks, relative size of Raman D and 2D peaks, thickness or depth, flexibility, adhesion, porosity, electrical conductivity, capacitance, absorption of organic solvents and aqueous solutions, hydrophilicity, EMI shielding, electrode quality, wettability, contact angle, anti-fouling. The method of claim 1.

14. The method of claim 1 , wherein the second laser beam modifies the carbon foam into the resulting carbon foam material as part of the process of exposing the carbon foam.

15. The method of claim 1 , wherein the second laser beam alters the morphology of the carbon foam as part of the process of creating and exposing the resulting carbon foam material.

16. The method of claim 1 , wherein the resulting carbon foam material is or comprises a multi-layer twisted carbon foam or a turbostratic carbon foam.

17. 10. The method of claim 1, wherein the resulting carbon foam material is or comprises a non-graphene carbon foam.

18. The method of claim 1, wherein the resulting carbon foam material is about 50 μm to 300 μm thick.

19. 10. The method of claim 1, wherein the resulting carbon foam material is or comprises a carbon foam having a spatial distribution of defects or basal plane defects at vacancy sites that results in high electrochemical reactivity.

20. 10. The method of claim 1, wherein the resulting carbon foam material has one or more of the following properties compared to conventional graphene foam made using conventional laser processes: more easily controlled thickness or depth, greater flexibility compared to very brittle graphene made using conventional laser processes, stronger adhesion to underlying flexible substrates, higher porosity, higher electrical conductivity, increased capacitance or charge storage, faster absorption of organic solvents and aqueous solutions, more hydrophilic, contact angle less than about 20°, enhanced anti-fouling properties, better EMI shielding, enhanced electrode quality.

21. The method of claim 1 , wherein the resulting carbon foam material is functionalized as a biosensor by adding a receptor that is specific for a target or analyte.

22. 10. The method of claim 1, wherein the resulting carbon foam material is functionalized as a biosensor by adding a receptor that is specific for a target or analyte and a linker that allows the receptor to attach to the resulting carbon foam material.

23. 10. The method of claim 1, comprising printing electrical contacts on or in the carbon precursor material before using the first laser beam or after using the first laser beam and the second laser beam.

24. 10. The method of claim 1, wherein the manufacturing method uses a combination of industry-standard, low-cost, and scalable (i) screen-printing technology and (ii) computer-controlled laser scanning technology.

25. The method of claim 1 , wherein the manufacturing method uses high speed, high volume reel-to-reel or reel-to-sheet production.

26. The method of claim 1 when used to manufacture a biosensor including a sensing electrode comprising the obtained carbon foam material.

27. 10. The method of claim 1, when used to manufacture a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each including the resulting carbon foam material, the method comprising printing electrical connection traces on each electrode and at least partially covering the electrodes and the connection traces with a printed dielectric.

28. 10. The method of claim 1, wherein when the resulting carbon foam material is used to manufacture biosensors including sensor electrodes, such as a working electrode and a counter electrode, each comprising the resulting carbon foam material at one manufacturing facility, the method comprises the further step of adding functionalizing groups to the working electrodes at the same manufacturing facility or at a different manufacturing facility.

29. 10. The method of claim 1, when used to manufacture a biosensor including sensor electrodes, such as a working electrode and a counter electrode, each comprising the resulting carbon foam material, the method comprising: (a) printing a carbon layer on the substrate; (b) printing electrical connection traces and a reference electrode; (c) printing a dielectric layer on the carbon layer, the electrical connection traces, and the reference electrode; and (d) fabricating a sensor electrode of the resulting carbon foam material.

30. 1. A laser-induced carbon foam comprising: A laser-induced carbon foam, which is a multilayer twisted carbon foam or turbostratic carbon foam, having a Raman signature characterized by D and G peaks, the G peak being significantly higher than the D peak, and having a carbon nano-onion surface morphology without stripes.

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