Synthesis, direct writing, and 3D printing graphene-like nanomaterials using brown's gas plasma torch

Abstract

Systems and methods for large-area synthesis and direct writing or 3D printing of graphene and graphene-like nanomaterials utilize an interaction between a Brown's gas plasma torch and carbon-containing materials. An apparatus generates a high-temperature Brown's gas that is capable of carbonizing, graphitizing, and exfoliating the carbon-containing substrate. A programmable motion system accurately positions the substrate relative to the plasma torch, enabling the deposition of patterned graphene-like structures or nanocomposites in a single-step. Optional lenses and masks may be used to control plasma spot size or restrict the exposure area. In addition, assist gas and nanopowder may be employed to tailor material composition. Operating at atmospheric pressure and producing only water vapor as a byproduct, the disclosed approaches present energy-efficient, environmentally safe, and scalable for various industrial applications.

Description

Docket BU128PCT SYNTHESIS, DIRECT WRITING, AND 3D PRINTING GRAPHENELIKE NANOMATERIALS USING BROWN’S GAS PLASMA TORCHINVENTORS:Valery SerbezovJason NaydenovSvetlin SerbezovJordan NaydenovKrassimir PetkovNikola ZlatanovCROSS REFERENCE TO RELATED PATENT APPLICATIONS

[0001] The present application claims priority benefit to co-pending and commonly-assigned U.S. Provisional Patent Application No. 63 / 746,870 and U.S. Provisional Patent Application No. 63 / 746,873, both filed on January 17, 2025 and listing as inventors Valery Serbezov, Jason Naydenov, Svetlin Serbezov, Jordan Naydenov, Krassimir Petkov, and Nikola Zlatanov, which application is herein incorporated by reference as to its entire content. Each reference mentioned herein is incorporated by reference herein in its entirety.A. Technical Field

[0002] The present disclosure relates to nanotechnology and additive technologies and more particularly to systems and methods for plasma torch-induced synthesis and printing (direct writing) of graphene, graphene-like nanomaterials, and nanocomposites using a Brown’s gas plasma torch-material interaction with natural and synthetic carbon-containing precursors, such as wood, paper or polymers.B. Background

[0003] Graphene is a novel two-dimensional (2D) material with unique properties, including strength, thermal conductivity, electrical conductivity, and large surface area, which makes graphene suitable for a wide range of applications in a various industries, such as energy, electronics, photonics, sensors and biomedicine. Modification of graphene may be achieved by incorporating functional groups or active substances into the graphene lattice. Such modifications can enhance desirable characteristics, introduce new functionalities, or suppress undesirable properties for a particular application. Additionally, nanocompositesDocket BU128PCT and hybrid nanocomposites — where each component forms hybrids with the others — often exhibit unique performance due to the resulting synergistic effects.

[0004] Modern industries require the development of new nanocomposite materials and corresponding technologies suitable for large-scale market implementation. Potential applications of nanocomposites cover many areas, including flexible electronics, medicine, pharmacy, mechanical components, energy devices, the automotive sector, environmental (air and water) remediation, sensor technology, antifouling surfaces, life sciences, defense, and aerospace. Currently, many structural modifications to graphene are performed after graphene formation using chemical vapor deposition (CVD) or wet chemical processes. For example, changing the wettability of graphene is done by synthesizing graphene oxide (GO) or fluorinating carbon atoms to reduce surface energy. Numerous methods have been tested to obtain GO or reduced GO (rGO), such as sonicating GO in various solvents, CVD-based 3D graphene formation or carbon nanotube hybrids.

[0005] Existing methods for patterning graphene-like nanomaterials include photolithography, soft lithography, transfer printing, direct ion patterning, laser scribing and ablation techniques. Other drawbacks of such multi-step methods include their inability to be combined with additive manufacturing technologies.

[0006] Additive manufacturing (AM) technologies or 2D / 3D printing or direct writing is a layer-by-layer fabrication approach that relies on computer-aided design (CAD) models, enabling streamlined production workflows. Various 3D printing methods have emerged for metals, alloys, ceramics, polymers, and biomaterials — even at micro- or nanoscale resolutions. Photolithography, screen printing, plasma spray, inkjet printing, and aerosol printing are also employed for depositing different materials. Inkjet printing has been explored for producing 2D / 3D graphene and graphene-like nanocomposites in a layer-by-layer fashion, but limitations include low resolution, multi-step procedures, and, in many cases, reliance on hazardous chemicals.

[0007] Laser-based 3D printing stands out for its precision in transferring different materials. Technologies for printing nanocomposites, including hybrid nanocomposites, with organic or inorganic matrices have also been developed. One such advancement — Laser Induced Graphene (LTG) — converts polyimide (PI) films into porous graphene under ambient conditions using a pulsed CO2laser. Although LIG significantly cuts production costs compared to traditional synthesis. The laser hardware is costly, requires extensive maintenance and demands specialized operating personnel. A pulsed CO2 laser can deposit aDocket BU128PCT large amount of photo-thermal energy in materials within a short time due to the long wavelength (10.6 pm) and relatively long pulse duration ( 14 jxs).

[0008] Further laser-induced methods, from continuous to ultrashort pulsed regimes and spanning wavelengths from infrared (IR) to ultraviolet (UV), have been tested on diverse carbon-containing materials, including wood and thermoplastic polymers. Variations like laser-assisted explosive synthesis and roll-to-roll LIG have been proposed to increase industrial feasibility. Despite LIG’s promise, specialized lasers impose ongoing expenses and operational complexity.

[0009] Additional processes exist for local graphene-like nanomaterial synthesis and direct writing / 3D printing, but they often require photoresists and multiple steps (e.g., e-beam exposure followed by high-temperature inert gas annealing).

[0010] Another known approach involves a modular print head featuring an inlet module, plasma with movable electrodes, and a nozzle for atomization. The print head can perform large-area deposition of metals, metal oxides, organics, or composite materials under atmospheric pressure, with mask-based patterning for refined geometry control. However, such methods typically necessitate changing and fine-tuning electrode setups, risk undesired arc discharge, and require multiple plasma parameters to be meticulously managed, thus leading to increased downtime, extended processing durations, and higher costs.

[0011] Accordingly, what is needed are systems and methods that overcome the existing limitations and provide low-cost, safe, fast alternatives that produce high-quality graphene and graphene-like functionalized materials, structures, and nanocomposites with desirable properties and for a wide range of industrial applications.SUMMARY OF INVENTION

[0012] Methods and systems herein provide for large-area synthesis and direct 2D / 3D printing of graphene and graphene-like nanomaterials, facilitated by a Brown’s gas (HHO) plasma torch that may adapt its temperature — ranging from about 140 °C to as high as 3500 °C — to match the requirements of the processed material, without emitting harmful ultraviolet radiation. The only byproduct of the process is water vapor, making it environmentally benign.

[0013] To carry out graphene synthesis and printing, a CNC coordinate system positions or may move a carbon-containing target material (e.g., wood, polymers, plastics) relative to the plasma torch. The torch may have a spot size from a few millimeters to a few centimeters, and scanning speeds can range from 100 mm / s to 1000 mm / s or higher, enablingDocket BU128PCT rapid coverage of large substrates. This setup allows for in situ graphitization and exfoliation as the high-temperature plasma releases energy into the substrate, causing localized carbonization, graphitization, and the formation of graphene-like layers. The process can be carried out under atmospheric conditions or in controlled atmospheres (e.g., oxidizing, inert, hydrogen-containing, or carbon-containing gas flow). A separate nozzle or inlet may supply powder or foil-based materials (metals, ceramics, polymers, etc.) to the torch interaction zone, forming hybrid nanocomposites in a single step. This capability enables doping, alloying, or multi-material integration during the creation of graphene-like structures. An optional stationary ionic lens, possibly magnetic, electrostatic, electromagnetic, or multipole, may be used to focus or shape the plasma, enabling more precise patterns at the micron or submicron scale. A high-temperature-resistant mask (e.g., graphite, tungsten, ceramics, or stainless steel) can be placed over the substrate to define the regions exposed to the plasma torch, producing complex 2D or 3D structures. The mask may be formed by laser processing or chemical etching to create micro- or nano-scale openings, figures, and functional structures.

[0014] This technique offers low-cost, energy-efficient synthesis and patterning, accommodating everything from large-area surfaces to micro-nanoscale features. The resulting graphene and graphene-like nanomaterials can be directly printed onto substrates for use in energy storage (supercapacitors, batteries), electronics, sensors, and microfluidic or bio-chemical devices. Because Brown’s gas combustion yields only water vapor, the method is environmentally friendly and industrially deployable. Operating with minimal specialized training, it is a one-step process that avoids the need for harsh chemicals or catalysts, providing high yield and reproducibility in an eco-conscious manner.

[0015] In summary, the invention leverages Brown’s gas plasma to achieve multifunctional, on-demand formation and printing of graphene-like materials, from small intricate patterns to large continuous areas, with optional doping or composite formation in real time. This novel approach opens up a wide range of applications, from micron-scale conductive electrodes and energy devices to wearable sensors and antiviral filtration systems, underscoring its versatility and potential impact across multiple industries.

[0016] In some aspects of the disclosure, a method for producing graphene and graphene-like nanomaterials by using brown’s gas plasma may comprise directing a brown’s gas plasma to a reaction zone may comprise a carbon-containing target, where interaction of the carbon-containing target with the brown’s gas plasma causes a thermal expansion thatDocket BU128PCT converts at least some of the carbon-containing target into atomic-level material; regulating a motion of the carbon-containing target relative to the brown’s gas plasma, disposing at least one of a mask or a stencil between the brown’ s gas plasma and the carbon-containing target to pattern an exposure area, and performing at least one of a 2D printing process or a 3D printing process to convert the atomic-level material into a graphene-like nanomaterial on the exposure area.

[0017] In some aspects, the method may further comprise controlling a spot size or a scanning speed at a plasma-target interface to facilitate a carbonization and a graphitization of the atomic-level material. An assist gas or a powder comprising a nanomaterial may be provided into the reaction zone to form a hybrid nanocomposite. The carbon-containing target may comprise an organic material, an inorganic material, a natural material, a synthetic material, wood, or a polymer. The mask may comprise an inorganic or an organic sheet or foil.

[0018] In some aspects of the disclosure, an apparatus for printing graphene or graphene-like nanomaterials by using brown’s gas plasma may comprise a first inlet configured to receive brown’s gas plasma generated from hydrogen and oxygen; a second inlet configured to receive at least one of a carbon-containing powder or an assist gas. The apparatus may further comprise a nozzle coupled to the first inlet, the nozzle configured to direct the brown’s gas to a reaction zone may comprise a carbon-containing target that has been patterned to define a target area, where interaction of the carbon-containing target with a brown’s gas plasma causes a thermal expansion that converts at least some of the carbon-containing target into atomic-level material and further converts the atomic-level material into a graphene-like nanomaterial on the target area.

[0019] In some aspects, the apparatus may further comprise an ion lens located between the nozzle and the target area to focus the brown’ s gas plasma. The ion lens may be configured to adjust a spot-size of the brown’s gas plasma, which may be provided at substantially atmospheric pressure. The carbon-containing target may comprise a mask that may comprise at least one of an inorganic foil or an organic foil. The assist gas, the carbon-containing powder, an inorganic powder, a natural powder, and / or a synthetic powder may be used to form a hybrid nanocomposite.

[0020] In some aspects of the disclosure, a system for printing graphene-like material by using brown’s gas plasma may comprise an apparatus that is configured to produce graphene-like material. The apparatus may comprise a first inlet configured to receiveDocket BU128PCT brown’s gas; a second inlet configured to receive at least one of a carbon-containing substance or an assist gas. The system may further comprise a nozzle configured to direct the brown’s gas to a reaction zone may comprise a carbon-containing target may comprise at least one of a mask or a stencil configured to pattern an exposure area, where interaction of the carbon-containing target with a brown’s gas plasma causes a thermal expansion that converts at least some of the carbon-containing target into atomic-level material and further converts the atomic-level material into a graphene-like nanomaterial on the exposure area. The system may further comprise a programmable motion system configured to regulate a motion of the carbon-containing target relative to the brown’s gas plasma; a gas generator configured to derive gas from hydrogen and oxygen to form the brown’s gas plasma, a power source configured to energize electrodes configured to ignite and generate the brown’s gas plasma, and one or more flow controllers configured to control an input flow of the brown’s gas and an input flow of the carbon-containing substance.

[0021] In some aspects, the programmable motion system may be configured to regulate a scanning-speed of the apparatus to facilitate a carbonization and a graphitization of the atomic-level material exfoliating. In some aspects, the carbon-containing substance or the assist gas may be used to form a hybrid nanocomposite.Docket BU128PCT BRIEF DESCRIPTION OF THE DRAWINGS

[0022] References will be made to embodiments of the invention, examples of which may be illustrated in the accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in the context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments. Items in the figures are not to scale.

[0023] FIG. 1 is a schematic representation of an HHO-plasma based process for producing graphene and graphene-like nanomaterials and nanocomposites for large-area direct writing or 3D printing, according to various embodiments of the present disclosure.

[0024] FIG. 2 is a schematic representation of an HHO-plasma based process for producing graphene and graphene-like nanomaterials using a focusing lens, according to various embodiments of the present disclosure.

[0025] FIG. 3 is a schematic representation of an HHO-plasma based process for producing graphene and graphene-like nanomaterials using an annealing process, according to various embodiments of the present disclosure.

[0026] FIG. 4A depicts a photograph illustrating a large-area graphene-like nanomaterial produced according to various embodiments of the present disclosure.

[0027] FIG. 4B - FIG. 4C depict SEM micrographs corresponding to FIG. 4A.

[0028] FIG. 5A - FIG. 5B depict EDX analyses results, according to various embodiments of the present disclosure.

[0029] FIG. 6A - FIG. 6B depict photographs illustrating a 2D graphene-like nanomaterial written directly on wood, according to various embodiments of the present disclosure.

[0030] FIG. 7A - FIG. 7C depict SEM micrographs corresponding to FIG. 6A and FIG. 6B.

[0031] FIG. 8A - FIG. 8C depict Raman spectra resulting from direct writing synthesis of graphene and graphene-like nanomaterials onto wood, according to various embodiments of the present disclosure.

[0032] FIG. 9A - FIG. 9B depict photographs illustrating direct writing onto polymer PS, according to various embodiments of the present disclosure.

[0033] FIG. 10A - FIG. 10B depict SEM micrographs corresponding to FIG. 9A and FIG. 9B.Docket BU128PCT

[0034] FIG. 11 is a photograph of a graphene aluminum - nanocomposite poly example, according to various embodiments of the present disclosure.

[0035] FIG. 12A - FIG. 12C depict SEM micrographs corresponding to FIG. 11.

[0036] FIG. 13 is a flowchart of an exemplary process for producing graphene-like nanomaterials using Brown’s gas plasma, according to various embodiments of the present disclosure.Docket BU128PCT DETAILED DESCRIPTION OF EMBODIMENTS

[0037] In the following description, for purposes of explanation, specific details are set forth in order to provide an understanding of the disclosure. It will be apparent, however, to one skilled in the art that the disclosure can be practiced without these details. Furthermore, one skilled in the art will recognize that embodiments of the present disclosure, described below, may be implemented in a variety of ways, such as a process, an apparatus, a system / device, or a method on a tangible computer-readable medium.

[0038] Components, or modules, shown in diagrams are illustrative of exemplary embodiments of the disclosure and are meant to avoid obscuring the disclosure. It shall be understood that throughout this discussion components may be described as separate functional units, which may comprise sub-units, but those skilled in the art will recognize that various components, or portions thereof, may be divided into separate components or may be integrated, including, for example, being in a single system or component. It should be noted that functions or operations discussed herein may be implemented as components. Components may be implemented in software, hardware, or a combination thereof.

[0039] Furthermore, connections between components or systems within the figures are not intended to be limited to direct connections. Rather, data between these components may be modified, re-formatted, or otherwise changed by intermediary components. Also, additional or fewer connections may be used. It shall also be noted that the terms “coupled,” “connected,” “communicatively coupled,” “interfacing,” “interface,” or any of their derivatives shall be understood to include direct connections, indirect connections through one or more intermediary devices, and wireless connections. It shall also be noted that any communication, such as a signal, response, reply, acknowledgment, message, query, etc., may comprise one or more exchanges of information.

[0040] Reference in the specification to “one or more embodiments,” “preferred embodiment,” “an embodiment,” “embodiments,” or the like means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the disclosure and may be in more than one embodiment. Also, the appearances of the above-noted phrases in various places in the specification do not necessarily all refer to the same embodiment or embodiments.

[0041] The use of certain terms in various places in the specification is for illustration and should not be construed as limiting. The terms “include,” “including,” “comprise,” “comprising,” and any of their variants shall be understood to be open terms, and anyDocket BU128PCT examples or lists of items are provided by way of illustration and shall not be used to limit the scope of this disclosure.

[0042] Any headings used herein are for organizational purposes only and shall not be used to limit the scope of the description or the claims. Each reference / document mentioned in this patent document is incorporated by reference herein in its entirety.

[0043] The present disclosure describes processes to obtain at industrial scale method for synthesis and printing / direct writing of graphene and graphene-like nanomaterials and nanocomposites by Brown gas plasma torch interaction with natural and synthetic carbon containing precursors (as wood, paper) and polymers.

[0044] As used herein, the term “carbon-containing substance” refers to any carbon-containing compound or substance composed primarily of carbon. The terms “plasma,” “HHO plasma torch,” and “plasma burner” may be used interchangeably to describe the high-energy ionized gas system that facilitates the synthesis process. The term “thermal zone” refers to the region where the plasma achieves a near or complete thermodynamic equilibrium.

[0045] The terms “graphene-like nanomaterials” and “graphene nanosheets” refer to crumpled graphene nanosheets having one or more layers of sp2-bonded carbon atoms arranged in a honeycomb lattice. Stacked nanosheets exhibiting curled, curved, or buckled morphologies result in a 3D structure. Depending on their specific characteristics, the synthesized materials may be referred to as “graphene nanoplatelets,” “graphene nanoflakes,” “few-layers graphene,” or simply “graphene.”

[0046] A fundamental principle in nanomaterial synthesis is the rapid introduction of energy into the system, followed by immediate cooling to prevent reaggregation. Systems and methods disclosed herein utilize a high-energy plasma generated from Brown’s gas, which is produced via water electrolysis. The Brown’s gas plasma interacts with carbon-based waste materials, such as charcoal, carbon black from used tires, and plastic waste, thus resulting in graphene formation through high-temperature exfoliation, followed by rapid thermal contraction.

[0047] Brown’s gas, named after researcher Yuli Brown, is generated by electrolysis, splitting water into hydrogen and oxygen. Unlike conventional fuels, Brown’s gas plasma has unique properties, including high ionization, electrical conductivity, and the ability to sustain combustion even in vacuum and underwater. It has a high energy density (~15,000 J / L), comparable to laser-material interaction; can reach temperatures of up to 4000 °C.Docket BU128PCT Additionally, Brown’s gas is implosive in nature, producing only water vapor as a byproduct, which makes it an environmentally safe and non-polluting energy source, extremely suitable for a sustainable circular economy.

[0048] The Brown’s gas plasma torch adapts to different carbon-containing materials, enabling effectively exfoliation of graphene layers from waste materials without requiring complex process adjustments. Additionally, this eliminates the need for harsh chemicals and catalysts, reduces batch-to-batch inconsistencies, and significantly lowers overall energy consumption, facilitating a single-step, high-yield graphene production process.

[0049] It shall be noted that while embodiments described herein are framed in the context of atmospheric environments, one skilled in the art will recognize that the concepts of the present disclosure are not so limited and may equally be used under superatmospheric, underpressure, or vacuum-controlled process conditions.

[0050] FIG. 1 is a schematic representation of an HHO-plasma based process for producing graphene and graphene-like nanomaterials over a large area, enabling direct writing or 3D printing, according to various embodiments of the present disclosure. As depicted, device 100 comprises HHO gas inlet 1, plasma nozzle 2, and plasma torch 3, which interact with a carbon-containing material 5 placed on programmable motion system 6, e.g., a CNC coordinate table. The synthesis results in graphene-like nanomaterial 4, and injection nozzle 10, which may be configured to introduce assist gas 8 and assist powder or nanopowder 9.

[0051] Plasma 3 may be generated by a Brown’s gas (HHO) generator (not shown), e.g., through electrolysis of distillated water. HHO gas is substantially a 2:1 mixture of hydrogen and oxygen that provides sufficient oxygen to sustain the plasma (or flame) reaction. Each mole of hydrogen burned releases approximately 241.8 kJ of energy. Resulting plasma 3 is highly ionized and its temperature may vary according to the material being processed. Advantageously, because Brown’s gas combustion yields only water vapor, it is considered nonpolluting and environmentally safe.

[0052] In system 100, HHO gas inlet 1 supplies plasma nozzle 2, which energizes the plasma torch 3. In embodiments, carbon-containing material 5, such as wood (e.g., sycamore or beech) or a polymer plate, is secured on motion system 6. The thickness of the plate may range from 3-5 mm to 10-30 mm, and its width and length may be sized appropriately for mounting on motion system 6.Docket BU128PCT

[0053] In operation, plasma 3 may reach temperatures of approximately 2500 °C or higher, sufficient to effectuate carbonization, graphitization, and exfoliation for synthesizing graphene-like nanomaterial 4. For large-area processing, the hot zone of plasma 3 may span several millimeters (e.g., 3-5 mm to 10-15 mm), and motion system 6 may be programmed to scan or “write” across the target surface. In embodiments, by adjusting the scanning program and speed, periodic or custom structures made of graphene-like material can be deposited or written onto the substrate.

[0054] It is noted that, in embodiments, the quality of the synthesized graphene-like nanomaterial 4 typically may depend on the interaction time between plasma 3 and material 5 and the specific composition of substrate 5. As an example, for wood, the percentage of cellulose is a critical factor; for polymers, it is primarily their carbon content that determines the effectiveness of the synthesis process.

[0055] FIG. 2 is a schematic representation of an HHO-plasma based process for synthesizing graphene and graphene-like nanomaterials using a focusing lens, according to various embodiments of the present disclosure. For clarity, components similar to those shown in FIG. 1 are labeled in the same manner. For purposes of brevity, a description or their function is not repeated here.

[0056] In embodiments, device 200 may comprise focusing lens 7, which may be positioned between plasma nozzle 2 and material 5, to adjust the dimensions of plasma torch 3. Lens 7 may be implemented as an electrostatic, a magnetic, an electromagnetic, or a multipole lens, depending on process requirements. In embodiments, by focusing plasma torch 3 to diameters ranging from micrometers to several millimeters, high-resolution direct writing of graphene and graphene-like structures becomes possible, e.g., for use in sensor and energy device applications.

[0057] In embodiments, the formation of predefined structures (HHO Plasma Induced Structures, HHO-PIS) on polymer substrates may involve heating the polymer above its glass transition or melting temperature and rapidly reaching a graphitization regime. Such processes advantageously rearrange the polymer chains and lead to desired carbonization, graphitization, and subsequent formation of graphene or graphene-like material. In embodiments, a relatively small amount of graphene-like nanomaterials may be added to a polymer to enhance its electrical, thermal, mechanical, and gas-barrier properties.

[0058] One advantage of this approach is the simultaneous synthesis of graphene and graphene-like nanomaterials within a polymer matrix, with user-defined environmentalDocket BU128PCT conditions in the process environment. In embodiments, various gases (e.g., inert, oxidizing, carbon-containing, or hydrogen) and powder materials (e.g., metals, oxides, alloys, ceramics, or semiconductors) may be fed sequentially, simultaneously, or in pulses through nozzle 10. The pressure of working gas 8 may range from 800 Torr to 1500 Torr. As a person of skill in the art will appreciate, flow control can be automated using mass flow controllers or flow meters.

[0059] In embodiments, liquids may be introduced through nozzle 10 to produce new graphene-based nanocomposites or hybrid nanocomposites, e.g., for optoelectronic or photonic applications.

[0060] FIG. 3 is a schematic representation of an HHO-plasma based process for producing graphene and graphene-like nanomaterials using an annealing process, according to various embodiments of the present disclosure. Same numerals as in FIG. 2 denote similar elements.

[0061] As in FIG. 2, device 300 comprises HHO gas 1, plasma nozzle 2, and plasma torch 3, which interacts with carbon-containing substrate 5 on motion system 6. Unlike device 200, focusing lens 7 may be absent.

[0062] In embodiments, system 200 facilitates 2D writing or 3D printing by employing mask or stencil 11 for pattern creation. Mask 11 may comprise thermally resistant material (e.g., steel, ceramic, brass, tungsten, graphite, or other high-temperature-resistant composites) capable of withstanding temperatures above 1000 °C. Micron- or nanostructures on mask 11 may be formed, e.g., by laser ablation, chemical etching, or mechanical drilling, depending on the chosen material. Once fabricated, mask 11 is disposed on carbon-containing substrate (e.g., wood or polymer). In embodiments, Brown’s gas plasma torch 3 interacts only with the exposed regions of substrate 5 through openings in mask 11, depositing, or converting the substrate material into graphene-like nanostructures in a controlled pattern. In embodiments, motion system 6 or torch 3 (or substrate 5) may be moved at processing speeds from 1 cm / s to 1000 cm / s and process parameters, such as energy transfer, environment composition (assist gases 8), and additive materials 9, may be fine-tuned to adjust the properties of the resultant graphene-like nanocomposites 4.

[0063] Once mask 11 is removed, printed or written graphene-like structures 4 remain on substrate 5. This flexible, one-step patterning method yields functional, preprogrammed graphene-like nanomaterials or hybrid nanocomposites 4. Advantageously, it isDocket BU128PCT environmentally friendly, requires minimal specialized personnel, and uses only water vapor as a byproduct.

[0064] Overall, the methods and systems disclosed herein provide low-cost, energyefficient, and scalable solutions for synthesizing and patterning graphene-like nanomaterials and nanocomposites in many potential applications. Direct-writing or 3D printing can be performed on a broad range of substrates ranging from large areas to micron-scale precision, using Brown’s gas plasma torches, assist gases, powders, and optional lenses or stencils.EXAMPLES

[0065] The following examples demonstrate various implementations of the disclosed systems and methods shown in FIG. 1 through FIG. 3. Characterization of the resulting graphene-like nanomaterials and nanocomposites was performed as follows:

[0066] Surface morphology of the product samples was examined using Scanning Electron Microscopy (SEM) in both secondary electron (SE) and backscattered electron (BE) imaging modes. Elemental analysis was conducted using Energy-dispersive X-ray analysis (EDX). And non-destructive chemical analysis, providing detailed information about chemical structure, phase composition, crystallinity, and molecular interactions, was carried out by using Raman spectroscopy with a Peltier-cooled CCD detector and a He-Ne laser operating at 633 nm and 0.5 mW power.EXAMPLE 1

[0067] In an exemplary embodiment of the method for synthesizing graphene and graphene-like nanomaterials through large-area direct writing or 3D printing (see FIG. 1), plasma torch 3 generated by a Brown’s gas source was directed at a beech wood pad 5 having the following dimensions: 50 mm in length, 25 mm in width, and 3 mm in thickness. Wooden pad 5 was secured on CNC coordinate table 6 featuring X-axis and Y-axis travels of 200 mm each, with a 1 pm resolution and a velocity range up to 100 mm / s. Table 1 lists the chemical composition of the beech wood substrate.

[0068] Table 1 Chemical composition of beech wood (percent of dry matter)Docket BU128PCT

[0069] It is noted that wood is a suitable carbon-containing material for producing graphene-like nanomaterials, as it can be directly converted into sp2-bonded carbon structures and be used in eco-friendly electronics and nanodevices. Advantageously, integrating carbon nanomaterials into wood-based boards improves their properties. Cellulose and lignin are the main components responsible for forming carbon, graphite, and graphene-like formation. When HHO plasma torch 3, having a spot size of 2 mm, impinges on wood target 5, its surface absorbs the energy released by the plasma. The energy release rate may be regulated by the scanning speed of CNC coordinate table 6. In this example, motion system 6 was programmed to move wood target 5 lengthwise at 2 mm intervals, without overlapping the lines of interaction. An experimentally determined scanning speed of 28 mm / s was used. Higher speeds resulted in reduced depth of conversion into graphite- and graphene-like nanomaterials. Synthesis occurred at atmospheric pressure and ambient temperature. A torch temperature of approximately 2500 °C was used to form graphene-like films. The resulting materials were analyzed by SEM, Raman spectroscopy, and EDX.

[0070] FIG. 4A depicts a photograph illustrating a large-area graphene-like nanomaterial produced according to various embodiments of the present disclosure. FIG. 4B and FIG. 4C depict corresponding SEM micrographs. The HHO plasma torch interaction with beech wood led to characteristic exfoliation and ordered thin layers typical of graphenelike nanomaterials. As Raman spectra in FIG. 8A - FIG. 8C confirm, due to the presence of oxygen from the atmosphere, primarily reduced graphene oxide (go) was formed. Corresponding EDX analysis results, shown in FIG. 5A and FIG. SB, indicate a significant increase in carbon content, confirming effective graphitization. The conversion process is not limited to beech; similar results were obtained with sycamore wood. Generally, any naturally occurring carbon-containing material in solid, liquid, or mixed states may serve as a suitable target.EXAMPLE 2Docket BU128PCT

[0071] This example illustrates a method for direct synthesis of graphene and graphenelike nanomaterials 4 and simultaneous 2D / 3D printing using Brown’ s gas plasma torch 3 and mask 11. Carbon-containing material — sycamore wood 5, known for its fine and even grain — served as the substrate, as depicted in FIG. 3. A 25 mm-wide, 50 mm-long, and 3 mm-thick wooden pad was disposed onto CNC coordinate table 6 that featured the same travel and resolution parameters described in Example 1.

[0072] Mask 11 made of 2 mm-thick graphite with structured holes of various shapes and diameters (1-2 mm to 5-6 mm) was placed over wood 5. These holes were machined to demonstrate the method’s simplicity. It is noted that more intricate patterns (including micro-and Nano scale features) may equally be used depending on application.

[0073] By varying the distance (3-6 mm) between HHO plasma torch 3 and substrate 5, HHO plasma torch 3 was focused to a spot size of 0.2 mm to 7.0 mm.

[0074] A preprogrammed scanning routine enabled CNC coordinate table 6 to move linearly at 28 mm / s with no stripe overlap. The 2500 °C plasma penetrated the openings in mask 11 to convert the exposed wood into 2D graphene-like nanomaterial 4, shown in FIG.6A and FIG.6B.

[0075] FIG. 7A - FIG. 7C depict SEM micrographs, corresponding to FIG. 6A and FIG. 6B, reveal well- arranged, graphitized layers typical of graphene-like nanomaterials. As in Example 1, oxygen from atmospheric air supported the formation of rGO, as shown by Raman spectra depicted in FIG. 8A - FIG. 8C.EXAMPLE 3

[0076] Although polymers have a wide range of applications in practice, they are limited by their physical and chemical properties. Graphene-like nanomaterials offer significant enhancements to polymers, such as improved electrical, thermal, and mechanical characteristics. This example demonstrates the direct synthesis of graphene-like nanomaterials 4 and the concurrent printing of 2D / 3D structures using HHO plasma torch 3 and stencil mask 11 on polymer substrate 5.

[0077] Similar to Example 2, this embodiment used polystyrene (PS) — a thermoplastic containing -90% carbon. A PS pad measuring 25 mm x 40 mm x 0.8 mm was attached to CNC coordinate table 6. Using the same graphite stencil mask 11, the scanning speed was raised from 28 mm / s to 70 mm / s to avoid excessive local heating as PS is more temperaturesensitive than wood. As illustrated by photographs FIG. 9A and FIG. 9B, at lower scanning speeds (28 mm / s), the polymer substrate experienced significant surface burning. FIG. 10A -Docket BU128PCT FIG. 10B depict SEM micrographs corresponding to FIG. 9A and FIG. 9B, which reveal new structural morphologies, indicative of polymer graphitization.

[0078] To fabricate hybrid nanocomposites comprising polymer 5, graphene-like nanomaterials 4, and metal nanoparticles, a similar arrangement was adopted with the exception that aluminum foil 12 was placed on stencil mask 11. Ablation of aluminum foil 12 by HHO plasma torch 3 formed metal nanoparticles that passed through mask 11 and bonded to polymer substrate 5, forming metal-graphene polymer nanocomposites.

[0079] FIG. 11 is a photograph of the resultant triple nanocomposites, and FIG. 12A -FIG. 12C depict SEM micrographs corresponding to FIG. 11 , which reveal the morphology of the newly formed materials. One potential application for such hybrid nanocomposites includes energy devices, such as nanogenerators that are configured to convert various physicochemical processes into electrical energy.

[0080] FIG. 13 is a flowchart of an exemplary process for producing graphene-like nanomaterials by using Brown’s gas plasma, according to various embodiments of the present disclosure. Process 1300 for producing graphene-like material may starts at step 1302, when a Brown’s gas plasma is directed to a reaction zone that comprises a carbon-containing target. In embodiments, the interaction of the carbon-containing target with the Brown’s gas plasma causes a thermal expansion that converts at least some of the carbon-containing substance into atomic-level material.

[0081] At step 1304, a programmable motion system may be used to regulate a motion of the carbon-containing target relative to the Brown’s gas plasma;

[0082] At step 1306, at least one of a mask or a stencil may be disposed between the Brown’s gas plasma and the carbon-containing target to pattern an exposure area.

[0083] Finally, at step 1308, a 2D or 3D printing process may be performed to convert the atomic-level material into a graphene-like nanomaterial on the exposure area.

[0084] One skilled in the art shall recognize that: (1) certain steps may optionally be performed; (2) steps may not be limited to the specific order set forth herein; (3) certain steps may be performed in different orders; and (4) certain steps may be done concurrently.

[0085] It will be appreciated by those skilled in the art that the preceding examples and embodiments are exemplary and not limiting to the scope of the present disclosure. It is intended that all permutations, enhancements, equivalents, combinations, and improvements thereto that are apparent to those skilled in the art upon a reading of the specification and a study of the drawings are included within the true spirit and scope of the present disclosure. ItDocket BU128PCT shall also be noted that elements of any claims may be arranged differently including having multiple dependencies, configurations, and combinations.

Claims

Docket BU128PCT CLAIMS WHAT IS CLAIMED IS:

1. A method for producing graphene and graphene-like nanomaterials using Brown’s gas plasma, the method comprisingdirecting a Brown’s gas plasma to a reaction zone comprising a carbon-containing target, wherein interaction of the carbon-containing target with the Brown’s gas plasma causes a thermal expansion that converts at least some of the carbon- containing target into atomic-level material;regulating a motion of the carbon-containing target relative to the Brown’s gas plasma;disposing at least one of a mask or a stencil between the Brown’s gas plasma and the carbon-containing target to pattern an exposure area; andperforming at least one of a 2D printing process or a 3D printing process to convert the atomic-level material into a graphene-like nanomaterial on the exposure area.

2. The method of claim 1, further comprising controlling at least one of a spot size or a scanning speed at a plasma-target interface to facilitate a carbonization and a graphitization of the atomic-level material.

3. The method of claim 1, further comprising providing at least one of an assist gas or a powder into the reaction zone to form a hybrid nanocomposite.

4. The method of claim 3, wherein the powder comprises a nanomaterial.

5. The method of claim 1, wherein the carbon-containing target comprises at least one of an organic material, an inorganic material, a natural material, a synthetic material, wood, or a polymer.

6. The method of claim 1, wherein the mask comprises at least one of an inorganic or an organic sheet or foil.

7. The method of claim 1, further comprising generating the Brown’s gas plasma from hydrogen and oxygen.

8. An apparatus for printing graphene or graphene- like nanomaterials using Brown’s gas plasma, the apparatus comprisinga first inlet configured to receive Brown’s gas;Docket BU128PCT a second inlet configured to receive at least one of a carbon-containing powder or an assist gas; anda nozzle coupled to the first inlet, the nozzle configured to direct the Brown’s gas to a reaction zone comprising a carbon-containing target that has been patterned to define a target area, wherein interaction of the carbon-containing target with a Brown’s gas plasma causes a thermal expansion that converts at least some of the carbon-containing target into atomic-level material and further converts the atomic-level material into a graphene-like nanomaterial on the target area.

9. The apparatus of claim 8, further comprising an ion lens located between the nozzle and the target area to focus the Brown’ s gas plasma.

10. The apparatus of claim 9, wherein the ion lens is configured to adjust a spot-size of the Brown’ s gas plasma, which is provided at substantially atmospheric pressure.

11. The apparatus of claim 8, wherein at least one of the assist gas, the carbon-containing powder, an inorganic powder, a natural powder, or a synthetic powder, is used to form a hybrid nanocomposite.

12. The apparatus of claim 9, wherein the carbon-containing target comprises a mask that comprises at least one of an inorganic foil or an organic foil.

13. A system for printing graphene-like material using Brown’s gas plasma, the system comprising:an apparatus configured to produce graphene-like material, the apparatus comprising:a first inlet configured to receive Brown’s gas;a second inlet configured to receive at least one of a carbon-containing substance or an assist gas;a nozzle configured to direct the Brown’s gas to a reaction zone comprising a carbon-containing target comprising at least one of a mask or a stencil configured to pattern an exposure area, wherein interaction of the carbon-containing target with a Brown’s gas plasma causes a thermal expansion that converts at least some of the carbon-containing targetDocket BU128PCT into atomic-level material and further converts the atomic-level material into a graphene-like nanomaterial on the exposure area; a programmable motion system configured to regulate a motion of the carbon- containing target relative to the Brown’s gas plasma;a gas generator configured to derive gas from hydrogen and oxygen to form the Brown’s gas plasma;a power source configured to energize electrodes configured to ignite and generate the Brown’s gas plasma; andone or more flow controllers configured to control an input flow of the Brown’s gas and an input flow of the carbon-containing substance.

14. The system of claim 13, wherein the programmable motion system is further configured to regulate a scanning-speed of the apparatus to facilitate a carbonization and a graphitization of the atomic-level material exfoliating.

15. The system of claim 13, wherein the at least one of the carbon-containing substance or the assist gas is used to form a hybrid nanocomposite.

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