Filtering supercapacitor based on nanoparticle-shaped graphene / foam metal and preparation method thereof

Abstract

The invention relates to the technical field of laser micro-nano manufacturing, and discloses a filtering supercapacitor based on nanoparticle-shaped graphene / foam metal and a preparation method thereof, and the preparation method comprises the following steps: preparing a cyanate resin / foam metal composite film by employing foam metal with an open pore structure and a liquid cyanate monomer; carrying out laser processing by adopting an intermediate infrared large-size light spot laser beam and an ultraviolet small-size light spot laser beam, and carrying out in-situ laser induction on the surface of the foam metal to grow the nanoparticle-shaped graphene so as to prepare a nanoparticle-shaped graphene / foam metal electrode raw material; cutting the electrode raw material into an electrode, and attaching a second mask; and preparing an interlayer type filtering supercapacitor. The conductivity of the generated nanoparticle-shaped graphene / foam metal thin film is as high as 909.09 S / cm, the prepared supercapacitor still keeps a relatively good capacitance behavior at a scanning rate of 2500V / s, the phase angle is as high as-70 degrees at 120Hz, the surface specific capacitance is 245 [mu] F / cm < 2 >, and meanwhile, the supercapacitor has a cut-off frequency as high as 3kHz and an RC time constant as low as 0.33 ms.

Description

Technical Field

[0001] This invention relates to the field of laser micro / nano manufacturing technology, and in particular to a supercapacitor for filtering based on nanoparticle-like graphene / foam metal and its preparation method. Background Technology

[0002] With the rapid miniaturization and high integration of portable smart electronic devices, traditional aluminum electrolytic capacitors, while dominating the filter capacitor market due to their advantages such as high voltage resistance and low cost, suffer from increasingly prominent inherent defects such as large size and insufficient specific capacitance, severely restricting the development of device miniaturization and planar integration technology. In contrast, micro supercapacitors, with their small size, high power density, fast charging and discharging speed, and excellent cycle stability, have become an ideal alternative to traditional energy storage devices, showing broad prospects, especially in flexible electronics, biomedicine, and the Internet of Things.

[0003] Currently, laser-processed electrodes face significant technical bottlenecks in filtering applications, essentially stemming from two core problems commonly found in carbon-based supercapacitors: insufficient electrode conductivity and slow ion diffusion kinetics. On one hand, laser-induced graphene electrodes suffer from poor conductivity due to low crystallinity and structural disorder; on the other hand, their disordered structure also restricts rapid ion migration. These two factors combined significantly reduce the electrode's cutoff frequency, failing to meet the stringent requirements of AC filtering for rapid charging and discharging and high-frequency response.

[0004] Therefore, a new method for manufacturing capacitors is urgently needed to solve the above-mentioned technical problems. Summary of the Invention

[0005] To address the aforementioned shortcomings, the present invention aims to propose a supercapacitor for filtering based on nanoparticle-shaped graphene / foam metal and its preparation method, thereby solving the problems of low yield, high cost, and complex process of traditional graphene preparation, which cannot meet the requirements of industrialization and large-scale production.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A method for fabricating a supercapacitor based on nanoparticle-like graphene / foam metal includes the following steps:

[0008] S1. A substrate is bonded to a glass substrate, and then a foam metal with an open structure is placed on the substrate. The outer periphery of the foam metal is then fixed and sealed by applying pressure to the first mask with a single-sided adhesive coating. Liquid cyanate monomer is then coated on the foam metal and cured by constant temperature heating to obtain a cyanate resin / foam metal composite film.

[0009] S2. The cyanate ester resin / foam metal composite film obtained in step S1 is irradiated with a mid-infrared large-size laser beam to generate a nanoparticle-shaped graphene / foam metal film; then the nanoparticle-shaped graphene / foam metal film is inverted and the substrate and glass substrate are separated by an ultraviolet small-size laser beam to obtain nanoparticle-shaped graphene / foam metal electrode raw material.

[0010] S3. Cut the nanoparticle-shaped graphene / foam metal electrode raw material obtained in step S2 into electrodes, clean and dry the electrodes, use laser ablation process to pattern the second mask, and attach the second mask to the electrode.

[0011] S4. Take at least two electrodes obtained in step S3, uniformly coat the surface of each electrode with ion gel electrolyte, and then transfer the electrodes to a vacuum chamber for vacuum treatment; after the ion gel electrolyte is transformed into a semi-solid state, align and attach several electrodes, apply pressure, and solidify and shape them at room temperature to obtain a sandwich-type filter supercapacitor.

[0012] Preferably, in step S1, the substrate is made of polyimide or polyethylene terephthalate, and the thickness of the substrate is 0.01 mm to 0.2 mm.

[0013] Preferably, in step S1, the substrate is made of polyimide or polyethylene terephthalate, and the thickness of the substrate is 0.01 mm to 0.2 mm.

[0014] Preferably, in steps S1 and S2, the first mask and the second mask are both made of polyimide or polyethylene terephthalate, and both have a thickness of 20-125 μm.

[0015] Preferably, the method further includes pretreating the solid cyanate monomer into a liquid cyanate monomer, placing the solid cyanate in a container, sealing the container, and then immersing the container in a water bath for heating. The water bath heating temperature is 50-70°C, and the time is 20-30 minutes.

[0016] Preferably, the liquid cyanate monomer is added by quantitative dripping in a proportional manner, with the amount of liquid cyanate monomer added per unit area of ​​the foamed metal being 20 mg / cm². 2 Up to 50 mg / cm 2 Preferably, in step S1, the heating and curing adopts a stepped heating method, with a heating temperature of 90-230℃ and a time of 7-8 hours.

[0017] Preferably, in step S2, the spot size of the mid-infrared large-size laser beam is 200-500μm, the scanning adopts a grating-type S-shaped overlapping path (serpentine scanning), the scanning speed is 80-120mm / s, the defocusing amount is +2-+4mm, the scanning pixel step size is 800-1200DPI, and the laser power is 7.5-25W.

[0018] Preferably, in step S2, the spot size of the ultraviolet small-size laser beam is 10μm to 20μm, the pulse center wavelength is 355nm, the pulse width is 5 to 20ps, the scanning adopts a left-to-right grating overlapping line-by-line path, the scanning speed is 600 to 1000mm / s, the focusing is performed, the scanning interval is 15 to 25.4μm, and the laser power is set to 7.5 to 16W.

[0019] A filter supercapacitor is prepared using the above-described preparation method.

[0020] The technical solution provided by this invention may include the following beneficial effects:

[0021] 1. The selected open-cell structure foam metal is a two-phase composite material composed of a metal matrix framework continuous phase and a pore continuous phase. Utilizing the liquid absorption characteristics of the pore continuous phase of the foam metal, liquid cyanate monomers spontaneously penetrate into the pore network of the foam metal under the action of capillary force. Then, the cyanate monomers are cured to polymerize and form a cyanate film that is bonded to the metal framework, thereby realizing the induced generation of nanoparticle-shaped graphene / foam metal films on the substrate.

[0022] 2. By inducing the formation of nanoparticle-shaped graphene / foam metal films on a substrate, the continuous phase of the metal matrix framework of the foam metal provides a continuous low-resistance electronic pathway. Combined with the tight composite of graphene, the interfacial resistance is reduced, and three-dimensional high-efficiency current collection is achieved, resulting in a conductivity of up to 909.09 S / cm for the nanoparticle-shaped graphene / foam metal films, which is 7.8 times that of graphene films.

[0023] 3. Thanks to the efficient current collection effect, low electrode resistance and excellent electrode / electrolyte interface contact brought by the continuous phase of the metal matrix framework of foam metal, the porous continuous phase of foam metal promotes electrolyte diffusion, and the nanoparticle graphene greatly shortens the ion diffusion distance and provides a high accessible surface area, so that the supercapacitor still maintains good capacitance behavior at a scan rate of up to 2500V / s.

[0024] 4. The oriented, interconnected nanopores or layered channels within graphene, along with the low tortuosity of its structure, allow ion migration paths to be nearly linear, rather than repeatedly detouring. This ordered structure creates low-torsion ion channels, enabling high-speed ion migration. Combined with ultra-low resistance, this significantly shortens charge-discharge relaxation time, allowing supercapacitors based on this material to achieve a phase angle as high as -70° at 120Hz and an areal capacitance of 245 μF / cm². 2 It also features a cutoff frequency of up to 3kHz and an RC time constant as low as 0.33ms, significantly exceeding the performance limits of traditional commercial aluminum electrolytic capacitors, thus effectively supporting demanding high-frequency filtering applications.

[0025] 5. The substrate is made of polyimide or polyethylene terephthalate, etc. The low thermal conductivity helps to maintain the high temperature environment at the irradiation point, while the appropriate thickness can provide sufficient heat capacity to buffer instantaneous thermal shock, making it an ideal sacrificial layer substrate for laser-induced graphene.

[0026] 6. The first and second masks are thin films made of polyimide (PI) or polyethylene terephthalate (PET). Due to their high absorption rate in the ultraviolet band, good thermal stability (especially PI), excellent mechanical flexibility, chemical stability, and mature laser processing suitability, they are the ideal and mainstream choice for flexible mask laser patterning. The hydrophobicity of the polyimide (PI) or polyethylene terephthalate (PET) films significantly reduces the risk of electrolyte permeation and short circuits caused by mask thinning or electrode roughness, improving device safety and reliability. They also enhance moisture resistance, contamination prevention, and inhibition of electrolyte creepage, thereby improving the environmental stability of the fabricated supercapacitor.

[0027] 7. By quantitatively adding liquid cyanate monomers, the capillary force of the foamed metal is fully utilized to achieve uniform, low-defect impregnation. This method also offers advantages such as ease of operation, low cost, and facilitating the formation of a good interfacial bond. The scraping coating step, as an auxiliary method, effectively promotes rapid surface distribution of the cyanate monomers and enhances capillary penetration.

[0028] 8. By employing a mid-infrared large-spot laser beam and a low laser scanning speed, this combination of parameters can induce graphene with optimal structural integrity and conductivity.

[0029] 9. Ultraviolet small-spot laser beam: The ultrafast pulsed ultraviolet laser with small spot size, high peak power, short pulse width, and high laser scanning speed can achieve selective ablation of cyanate ester resin / foam metal composite film through this parameter combination, so that the adhesive layer of the substrate is fully carbonized. When peeling cyanate ester resin / foam metal composite film from glass substrate, the morphology and electrical properties of the surface material are kept stable. Attached Figure Description

[0030] Figure 1 This is a schematic flowchart of a preparation method according to an embodiment of the present invention.

[0031] Figure 2 This is a schematic diagram illustrating the fabrication technique of nanoparticle-shaped graphene / foam metal film according to an embodiment of the present invention.

[0032] Figure 3 This is an exploded view of the sandwich-type filter supercapacitor prepared according to Embodiment 1 of the present invention.

[0033] Figure 4 This is a schematic diagram of the structure of the series array sandwich filter supercapacitor prepared in Embodiment 2 of the present invention.

[0034] Figure 5 This is a schematic diagram of the surface microstructure of the nanoparticle-shaped graphene / foam metal film prepared in Example 1 of the present invention;

[0035] Figure 6 This is the CV curve of the sandwich-type filter supercapacitor prepared in Example 1 of the present invention at a scan rate of 2500V / s;

[0036] Figure 7 This is the CV curve of the series array sandwich filter supercapacitor prepared in Embodiment 2 of the present invention at a scan rate of 5000V / s;

[0037] Figure 8 This is a Bode curve of the sandwich-type filter supercapacitor prepared in Embodiment 2 of the present invention;

[0038] Figure 9 This is a comparison chart of the filtering performance of commercial aluminum electrolytic capacitors and the sandwich-type supercapacitor prepared in Example 1 of this invention;

[0039] Figure 10 This is a comparison chart of the filtering performance of commercial aluminum electrolytic capacitors and the series array sandwich filter supercapacitor prepared in Example 2 of this invention.

[0040] Figure 11 This is the XRD pattern of the nanoparticle-shaped graphene / nickel foam film prepared in Example 2 of the present invention.

[0041] Figure 12 This is the Raman spectrum of the nanoparticle-shaped graphene / nickel foam film prepared in Example 2 of the present invention.

[0042] Wherein: electrode 1, second mask 2, electrolyte 3. Detailed Implementation

[0043] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0044] In the description of this invention, it should be understood that the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, features defined with "first" and "second" may explicitly or implicitly include one or more of these features, used to distinguish and describe features, without any order or emphasis.

[0045] In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0046] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0047] The embodiments of the present invention are described below with reference to the accompanying drawings.

[0048] like Figure 1 and Figure 2 As shown, a method for fabricating a supercapacitor based on nanoparticle-like graphene / foam metal includes the following steps:

[0049] S1. A substrate is bonded to a glass substrate, and then a foam metal with an open structure is placed on the substrate. The outer periphery of the foam metal is then fixed and sealed by applying pressure to the first mask with a single-sided adhesive coating. Liquid cyanate monomer is then coated on the foam metal and cured by constant temperature heating to obtain a cyanate resin / foam metal composite film.

[0050] S2. The cyanate ester resin / foam metal composite film obtained in step S1 is irradiated with a mid-infrared large-size laser beam to generate a nanoparticle-shaped graphene / foam metal film; then the nanoparticle-shaped graphene / foam metal film is inverted and the substrate and glass substrate are separated by an ultraviolet small-size laser beam to obtain nanoparticle-shaped graphene / foam metal electrode raw material.

[0051] S3. Cut the nanoparticle-shaped graphene / foam metal electrode raw material obtained in step S2 into electrodes, clean and dry the electrodes, use laser ablation process to pattern the second mask, and attach the second mask to the electrode.

[0052] S4. Take at least two electrodes obtained in step S3, uniformly coat the surface of each electrode with ion gel electrolyte, and then transfer the electrodes to a vacuum chamber for vacuum treatment; after the ion gel electrolyte is transformed into a semi-solid state, align and attach several electrodes, apply pressure, and solidify and shape them at room temperature to obtain a sandwich-type filter supercapacitor.

[0053] Using the above preparation method, the selected open-cell foam metal is a two-phase composite material composed of a continuous phase of metal matrix framework and a continuous phase of pores. Utilizing the liquid absorption properties of the continuous phase of the foam metal, liquid cyanate monomers spontaneously infiltrate into the pore network of the foam metal under capillary action. The cyanate monomers are then cured, causing them to polymerize and form a cyanate film bonded to the metal framework, thus inducing the formation of nanoparticle-like graphene / foam metal films on the substrate. There are no inherent process limitations on the electrode size; the cutting size is entirely determined according to the capacitor application requirements. For example, the electrode size range for a single capacitor is 4mm×5mm to 6mm×7mm; the electrode size range for a series capacitor is 4mm×10mm to 6mm×12mm. The patterning of the second mask is based on the complex pattern required for the final product.

[0054] By using a first mask, it is ensured that the liquid cyanate monomer only wets and solidifies within the desired foam metal area, forming a well-defined composite film. After pressurizing and bonding the first mask, observe the contact line between the first mask and the foam metal and substrate. It should be a continuous, gap-free, wrinkle-free, bubble-free, and tightly bonded line. Any visible gaps or raised edges indicate poor sealing. Simultaneously check that the mask is flatly bonded without any localized bulges or detachments.

[0055] Conventional methods for inducing graphene film formation utilize small-spot CO2 infrared lasers (wavelength 10.6 μm). While conventional laser processes aim to create continuous graphene structures, forming uniformly dispersed nanoparticle-like graphene on a metal framework requires a more uniform thermal field and specific reaction conditions. The highly localized and non-uniform thermal field generated by small-spot scanning makes precise control difficult, easily leading to uneven products (some areas over-fire into continuous graphene or carbides, while others remain unreacted). The method of this invention, however, uses a large-spot mid-infrared laser beam to irradiate a cyanate ester resin / foam metal composite film, in-situ laser-induced growth of nanoparticle-like graphene on the foam metal surface, solving the problem of precisely controlling the formation of uniformly dispersed nanoparticle-like graphene on a metal framework.

[0056] Conventional methods for separating substrates utilize small-spot ultraviolet lasers, incident from the substrate side, precisely targeting the interface sacrificial layer to achieve separation through ablation or weakening of the interface. However, ultraviolet lasers experience scattering when penetrating porous films, necessitating higher energy densities and easily ablating surface graphene nanoparticles or melting the metal framework. Furthermore, laser energy impacts can cause brittle foam metal structures to rupture and graphene to detach. In contrast, the preparation method of this invention uses an ultraviolet laser to ablate the bottom adhesive layer of the substrate through a glass substrate, avoiding damage to the surface functional layer and maintaining the stability of the surface material's morphology and electrical properties.

[0057] By inducing the formation of nanoparticle-shaped graphene / foam metal films on a substrate, the continuous phase of the metal matrix framework of the foam metal provides a continuous low-resistance electronic pathway. Combined with the tight composite of graphene, the interfacial resistance is reduced, and three-dimensional high-efficiency current collection is achieved. As a result, the conductivity of the nanoparticle-shaped graphene / foam metal films reaches as high as 909.09 S / cm, which is 7.8 times that of graphene films.

[0058] Thanks to the efficient current collection effect, low electrode resistance, and excellent electrode / electrolyte interface contact brought by the continuous phase of the metal matrix framework of foam metal, the porous continuous phase of foam metal promotes electrolyte diffusion, and the nanoparticle-shaped graphene greatly shortens the ion diffusion distance and provides a high accessible surface area, enabling the supercapacitor to maintain good capacitive behavior at a scan rate of up to 2500V / s.

[0059] The oriented, interconnected nanopores or layered channels within graphene, along with the low tortuosity of its structure, allow ion migration paths to be nearly linear, rather than repeatedly meandering. This ordered structure creates low-torsion ion channels, enabling high-speed ion migration. Combined with ultra-low resistance, this significantly shortens charge-discharge relaxation time, allowing supercapacitors based on this material to achieve a phase angle as high as -70° and a surface capacitance of 245 μF / cm at 120 Hz. 2It also features a cutoff frequency of up to 3kHz and an RC time constant as low as 0.33ms, significantly exceeding the performance limits of traditional commercial aluminum electrolytic capacitors, thus effectively supporting demanding high-frequency filtering applications.

[0060] Preferably, in step S1, the glass substrate is made of borosilicate glass or fused silica, and the thickness of the glass substrate is 1 mm to 3 mm.

[0061] Borosilicate glass or fused silica has high transmittance in the ultraviolet band, which can maximize the effective utilization of laser energy, ensure that the laser can efficiently penetrate the glass substrate, accurately act on the target layer, and achieve controllable peeling of the subsequent mask.

[0062] A glass substrate thickness greater than 1 mm ensures mechanical stability and thermal buffering capacity, preventing breakage and thermal runaway. A glass substrate thickness less than 3 mm facilitates control of laser attenuation and thermal stress, ensuring energy transfer efficiency.

[0063] Preferably, in step S1, the substrate is made of polyimide or polyethylene terephthalate, and the thickness of the substrate is 0.01 mm to 0.2 mm.

[0064] Under the same processing conditions, higher thermal conductivity helps improve the uniformity and graphitization degree of the final graphene surface. The substrate type and thickness directly affect the thermal conductivity of the composite material. Using low thermal conductivity materials such as polyimide or polyethylene terephthalate can effectively limit the diffusion of laser energy, making it highly localized at the irradiation point, thereby generating ultra-high temperatures exceeding 800°C to meet the graphitization requirements. In addition, the thickness of the substrate has a significant impact on this process. If it is too thin, insufficient heat capacity will cause the temperature to rise sharply above the vaporization threshold of 500°C, triggering graphene oxidation and shedding; if it is too thick, the increased thermal resistance will cause the energy to be absorbed by the deep non-reactive regions, resulting in insufficient surface temperature to inhibit the cyanate ester reaction. Therefore, the combination of low thermal conductivity and moderate thickness is the key to achieving controllable thermal localization. Low thermal conductivity helps maintain the high-temperature environment at the irradiation point, while a suitable thickness can provide sufficient heat capacity to buffer instantaneous thermal shock, making it an ideal sacrificial layer substrate for laser-induced graphene.

[0065] Preferably, in step S1, the foam metal is foam nickel or foam copper, and the thickness of the foam metal is 0.1 mm to 0.3 mm.

[0066] The unique catalytic activity of nickel foam can significantly improve the efficiency of laser-induced graphene formation, reducing the pyrolysis temperature by approximately 200°C; while the extremely low resistivity (1.7 μΩ·cm) and cost advantage of copper foam are more suitable for large-scale production. When the thickness of the foam metal is less than 0.1 mm, the pore wall structure lacks strength and is prone to tearing mechanical failure under laser thermal stress; when the thickness exceeds 0.3 mm, multiple scattering of the mid-infrared laser in the metal framework leads to energy attenuation, and the deep cyanate ester resin cannot reach the graphene formation threshold temperature, resulting in a decrease in energy utilization.

[0067] Preferably, in steps S1 and S2, the first mask and the second mask are both made of polyimide or polyethylene terephthalate, and both have a thickness of 20-125 μm.

[0068] The first and second masks are thin films made of polyimide (PI) or polyethylene terephthalate (PET). Due to their high absorption rate in the ultraviolet band, good thermal stability (especially PI), excellent mechanical flexibility, chemical stability, and mature laser processing suitability, they are the ideal and mainstream choice for flexible mask laser patterning. The hydrophobicity of the polyimide (PI) or polyethylene terephthalate (PET) films significantly reduces the risk of electrolyte permeation and short circuits caused by mask thinning or electrode roughness, improving device safety and reliability. They also enhance moisture resistance, contamination prevention, and inhibition of electrolyte creepage, thereby improving the environmental stability of the fabricated supercapacitors.

[0069] If the first mask is too thick, it will create obvious steps, causing abnormal thickening at the edges due to surface tension during resin coating. Simultaneously, the flexibility of the first mask decreases, making it difficult to tightly adhere to the joint between the foam metal and the substrate, resulting in a high risk of poor sealing. If the first mask is too thin, it will lack mechanical strength, making it easily scratched or torn by the foam metal. It also lacks support, making it difficult for the adhesive layer to effectively fill gaps, resulting in poor sealing reliability. Furthermore, an excessively thin first mask is too soft and prone to wrinkling, making operation difficult.

[0070] It is worth noting that the thickness of the second mask has a decisive impact on the filtering supercapacitor. A thinner second mask can significantly shorten the electrolyte thickness, thereby shortening the ion migration path, reducing ion resistance, and thus improving high-frequency response characteristics. However, excessive thinning will sacrifice mechanical strength, and when the thickness of the second mask is less than 20 μm, short circuits are easily caused by electrode roughness. On the other hand, a second mask thickness greater than 125 μm will directly increase the electrolyte layer thickness, lengthen the ion migration path, and increase resistance, severely degrading high-frequency response performance and failing to meet filtering requirements.

[0071] Preferably, in steps S1 and S2, both the first and second masks are made of polyethylene naphthalate (PEN), and the mask thickness is 20-125 μm. In another embodiment, PEN is used as the mask material, which has superior performance but is more expensive, making it suitable for applications that are somewhat cost-sensitive but have higher requirements than PET.

[0072] Preferably, the method further includes pretreating the solid cyanate monomer into a liquid cyanate monomer, placing the solid cyanate in a container, sealing the container, and then immersing the container in a water bath for heating. The water bath heating temperature is 50-70°C, and the time is 20-30 minutes.

[0073] Cyanate ester monomers are solid at room temperature and require liquefaction treatment before they can be effectively impregnated in foamed metal. Using sealed containers can suppress cyanate ester volatilization, and immersion in a water bath further seals the container, ensuring a tight seal. The water bath uses water convection to evenly transfer heat to the container walls and then to the cyanate ester, preventing localized overheating / overcooling. Water's high specific heat capacity allows the water bath heating medium to buffer temperature fluctuations.

[0074] When the water bath temperature is too low, the cyanate ester cannot be completely melted, resulting in insufficient fluidity. When the water bath temperature is too high, the viscosity of the cyanate ester becomes too low, leading to excessive fluidity during the curing process, which can easily contaminate the mold or equipment. When the water bath time is too short, the cyanate ester is not sufficiently preheated, resulting in excessively high viscosity and insufficient fluidity. This can easily cause gaps during curing, and if microbubbles or moisture in the cyanate ester do not escape, pinholes or voids can easily form after curing. When the water bath time is too long, the cyanate ester will undergo partial cross-linking (pre-curing) during the heating stage, resulting in an abnormally high viscosity.

[0075] Preferably, the liquid cyanate monomer is added by quantitative dripping in a proportional manner, with the amount of liquid cyanate monomer added per unit area of ​​the foamed metal being 20 mg / cm². 2 Up to 50 mg / cm 2 .

[0076] Place the sample with the foamed metal fixed on a balance. Use a dropper to add liquid cyanate monomer, controlling the dropping speed: each drop should be spaced more than 2 seconds apart, with the droplets falling freely (not spraying); control the dropping height: the tip of the dropper should be less than 1 cm from the surface of the foamed metal to avoid splashing or localized accumulation caused by droplet impact; control the dropping path: during the dropping process, move the dropper at a uniform speed in a zigzag pattern to cover the entire effective area. After dropping, immediately use a fine scraper to gently scrape the sample surface. If you can see a slight overflow of cyanate and the scraping marks disappear within 10 seconds, the scraping is complete.

[0077] If the amount of liquid cyanate monomer added is less than 20 mg / cm³ 2Cyanate esters are difficult to completely wet the pores of the foamed metal, resulting in uneven distribution of the laser-induced graphene layer and reduced charge transport efficiency.

[0078] If the amount of liquid cyanate monomer added is higher than 50 mg / cm³ 2 Excessive cyanate esters can submerge the foam metal skeleton, preventing it from being effectively exposed to the laser irradiation area, thus weakening the construction effect of the three-dimensional conductive network and ultimately affecting the filtering performance.

[0079] By quantitatively adding liquid cyanate monomers, the capillary force of the foamed metal is fully utilized to achieve uniform, low-defect impregnation, which also has the advantages of simple operation, low cost, and good interfacial bonding. The scraping coating step, as an auxiliary method, effectively promotes the rapid surface distribution of cyanate monomers and improves the capillary penetration effect.

[0080] Preferably, in step S1, the heating and curing adopts a stepped heating method, with a heating temperature of 90-230℃ and a time of 7-8 hours.

[0081] By employing a stepped heating method, the resin viscosity is sufficiently reduced in the low-temperature range (90-120℃) to achieve complete filling of the foam metal pores and avoid residual air bubbles. In the medium-temperature range (150-180℃), the heat of reaction is released in stages, with a core-to-surface temperature difference of <5℃, preventing thermal decomposition of the resin. In the high-temperature range (200-240℃), the complete cross-linking of the triazine ring network is promoted. This addresses the problems of: during isothermal curing, the initial high viscosity of the resin cannot be sufficiently reduced at a constant temperature, resulting in insufficient capillary force and difficulty in completely wetting the foam metal; and during uniform heating, the resin exhibits a sudden viscosity drop inflection point at 120–150℃, which is instantly bypassed by uniform heating, losing the opportunity for deep wetting. Furthermore, the resin viscosity increases exponentially after 160℃, and uniform heating lacks a pressure-holding and venting stage, causing the gas escape rate within the pores to lag behind the gelation rate, resulting in a high rate of residual air bubbles.

[0082] Furthermore, if the curing temperature is too high, the high temperature increases the curing reaction rate, and concentrated exothermic reactions lead to localized carbonization of the cyanate ester, releasing toxic gases. Excessive cross-linking caused by high temperatures reduces the free volume of the molecular chains, decreasing impact strength, elongation at break, and significantly increasing product brittleness. If the curing temperature is too low, the cyanate ester will not cure completely, and insufficient molecular kinetic energy will cause cross-linking to stagnate, resulting in residual stickiness on the surface, loss of wear resistance, and long-term reliability degradation. Unreacted monomers will slowly migrate and precipitate, accelerating product aging and contaminating surrounding components. If the curing time is too short, the cyanate ester will appear hardened, but the internal cross-linking degree will be less than 80%. It may pass short-term tests, but its performance will collapse after long-term use. Internal stress concentration in the cyanate ester, and surface curing shrinkage restricting continued internal shrinkage, easily induces spontaneous cracking. If the curing time is too long, the cyanate ester will experience over-curing degradation, molecular chain oxidation, decreased tensile strength, yellowing, and waste of energy and costs. Ineffectively extending the curing time increases costs.

[0083] Preferably, in step S2, the spot size of the mid-infrared large-size laser beam is 200-500μm, the scanning adopts a grating-type S-shaped overlapping path (serpentine scanning), the scanning speed is 80-120mm / s, the defocusing amount is +2-+4mm, the scanning pixel step size is 800-1200DPI, and the laser power is 7.5-25W.

[0084] This combination of parameters can induce graphene with optimal structural integrity and electrical conductivity.

[0085] It is worth mentioning that by employing a large-spot mid-infrared laser beam and a low laser scanning speed, the cyanate ester resin / foam metal composite film can be graphitized. Cyanate ester material itself has a high absorption rate for infrared laser wavelengths. Although the surface of the cyanate ester material is covered by foam metal after curing, the three-dimensional interconnected pore network of the foam metal allows the mid-infrared CO2 laser to partially penetrate the gaps in the metal skeleton and directly act on the internal resin layer. The laser energy forms a localized high-temperature field on the resin surface, while the high thermal conductivity of the foam metal causes heat to diffuse rapidly along the metal skeleton, forming a dynamically balanced temperature gradient. The central region of the laser spot heats up instantaneously to over 2000 degrees Celsius due to concentrated energy, triggering violent pyrolysis and graphitization of the resin. This results in the in-situ growth of nanoparticle-like graphene on the foam metal surface, while the edges of the adjacent pores remain at a relatively low temperature due to metal heat dissipation, inhibiting excessive oxidation and stabilizing the graphitization reaction process.

[0086] In a more preferred embodiment, the mid-infrared large-size laser beam is provided by a mid-infrared CO2 laser or a visible light semiconductor laser. Preferably, a mid-infrared CO2 laser with a laser power of 16W, a defocusing amount of +2mm, a scanning speed of 100mm / s, and a scanning pixel step size of 1000DPI (i.e., a scanning spacing of 25.4μm) is used to prepare the supercapacitor with the best performance.

[0087] Preferably, in step S2, the spot size of the ultraviolet small-size laser beam is 10μm to 20μm, the pulse center wavelength is 355nm, the pulse width is 5 to 20ps, the scanning adopts a left-to-right grating overlapping line-by-line path, the scanning speed is 600 to 1000mm / s, the focusing is performed, the scanning interval is 15 to 25.4μm, and the laser power is set to 7.5 to 16W.

[0088] This parameter combination enables selective ablation of cyanate ester resin / foam metal composite films, allowing for thorough carbonization of the substrate's adhesive layer. This maintains the stability of the surface material's morphology and electrical properties during the peeling of the cyanate ester resin / foam metal composite film from the glass substrate.

[0089] The ultraviolet small-spot laser beam employs an ultrafast pulsed ultraviolet laser with a small spot size, high peak power, short pulse width, and high laser scanning speed. The purpose is to utilize the instantaneous high peak power characteristic of the ultrafast pulsed laser to complete bond breakage before energy diffusion, thus avoiding the expansion of the heat-affected zone. At the same time, it causes the adhesive layer to undergo a transformation chain from dehydrogenation and aromatic cyclization to condensation at an instantaneous high temperature (>1500K), ultimately forming a continuous carbon network. The glass substrate has a high thermal diffusivity, which limits the temperature rise of the substrate to below 80℃.

[0090] In a more preferred embodiment, the small-sized ultraviolet laser beam is provided by an ultraviolet ultrafast laser or an ultraviolet nanolaser, preferably an ultraviolet picosecond laser with a pulse center wavelength of 355nm and a pulse width of 10ps. The parameters are set as follows: scanning speed of 800mm / s, focusing, scanning spacing of 25.4μm, and laser power of 10.5W. The supercapacitor prepared has the best performance.

[0091] Preferably, in step S3, the edge of the coated ion gel electrolyte covers the inner edge of the second mask to form a safety gap, the width of which is 0.8mm-1.2mm.

[0092] When coating the electrolyte, it should contact and cover the inner edge of the second mask to ensure complete coverage of the coating area. Simultaneously, due to the hydrophobic properties of the second mask, the electrolyte is confined within the coating area by surface tension, preventing it from overflowing the coating boundary. A safety clearance less than 0.8 mm will result in insufficient sealing strength, while a clearance greater than 1.2 mm will affect the effective electrode area.

[0093] Preferably, in step S3, after the second mask is attached to the electrode, pressure needs to be repeatedly applied to the second mask. In a specific embodiment, pressure is applied to the mask using tweezers or an acrylic rod to ensure that the second mask adheres tightly to the surface of the electrode, preventing electrolyte leakage and isolating the gas infiltration path, thus eliminating the risk of short circuits caused by interface gaps.

[0094] Preferably, in step S3, the electrode is cleaned using anhydrous ethanol and deionized water. The cleaned electrode is then dried at 50°C to 90°C for 10 to 30 minutes.

[0095] Preferably, in step S4, the ionogel electrolyte is made of PVA / H3PO4, PVA / H2SO4, or PVA / LiCl.

[0096] The polyvinyl alcohol (PVA)-based semi-solid gel electrolyte possesses excellent leak-proof and solid-state properties, greatly enhancing safety and ease of encapsulation; its flexible gel structure has a certain degree of flexibility and elasticity, allowing it to be bent and stretched; and it can provide more stable electrode / electrolyte interface contact.

[0097] Preferably, in step S4, the vacuum level of the vacuuming process is maintained at -0.9MPa to -0.7MPa, and the processing time is 30 to 50 minutes.

[0098] It is worth noting that the key to vacuum treatment is to completely remove gas molecules from the electrode micropores and gel electrolyte, ensuring a bubble-free and tight contact between them. Any residual bubbles at the electrode / electrolyte interface or inside the gel will significantly increase the system resistance and hinder effective ion interfacial transport, thus affecting the filtering effect of the device. In a specific embodiment, a vacuum drying oven is used for vacuum treatment.

[0099] A filter supercapacitor is prepared using the above-described preparation method.

[0100] The supercapacitor fabricated using this method maintains good capacitive behavior even at scan rates up to 2500V / s, making it suitable for the rapid miniaturization and high integration of portable smart electronic devices. Other characteristics are detailed below. Figures 5-12 .

[0101] Example 1

[0102] S1. A substrate is bonded to a glass substrate, and then a foam metal with an open structure is placed on the substrate. The outer periphery of the foam metal is then fixed and sealed by applying pressure to the first mask with a single-sided adhesive coating. Liquid cyanate monomer is then coated on the foam metal and cured by constant temperature heating to obtain a cyanate resin / foam metal composite film.

[0103] The substrate consisted of a 50mm × 50mm polyimide film with a thickness of 125μm, which was flatly attached to a 50mm × 50mm glass substrate with a thickness of 2mm. The sample surface was then cleaned with anhydrous ethanol and rinsed with deionized water. After cleaning, it was dried in a 60℃ vacuum oven for 15 minutes to remove residual solvent and moisture. A 33mm × 33mm, 0.1mm thick copper foam was placed centered on the cleaned sample surface. A 100μm thick square-ring polyimide mask was used to position and fix the copper foam area, ensuring precise control of the area for subsequent operations. Simultaneously, the solid cyanate monomer was pretreated by placing it in a sealed container and heating it in a 70℃ water bath for 30 minutes to convert it into a homogeneous liquid cyanate monomer for use. The sample assembly with the fixed copper foam was placed on a balance tray, and 0.3g of liquid cyanate monomer was accurately weighed and slowly added dropwise to the copper foam area. The surface was then coated with a small stick to completely cover the copper foam with liquid cyanate monomer and uniformly impregnate it within the pores of the copper foam. Finally, the entire sample was transferred to a preheated heating stage. A temperature program was set to progressively increase the sample temperature from an initial 90°C to 230°C over 8 hours for curing. The initial temperature was 90°C for 30 minutes to fully impregnate the metal foam pores; then the temperature was increased to 120°C over 30 minutes and held for 30 minutes to activate the prepolymerization reaction and initiate bubble removal; the temperature was then increased to 150°C over 30 minutes and held for 30 minutes to complete dynamic venting; subsequently, the temperature was increased to 200°C over 30 minutes and held for 2 hours to control the main crosslinking exothermic peak; finally, the temperature was increased to 230°C over 30 minutes and held for 2 hours to strengthen the triazine ring network and ensure complete reaction. After the reaction, the sample was allowed to cool naturally to room temperature on the heating stage, yielding a cyanate resin / copper foam composite film.

[0104] S2. The cyanate ester resin / foam metal composite film obtained in step S1 is irradiated with a mid-infrared large-size laser beam to generate a nanoparticle-shaped graphene / foam metal film; then the nanoparticle-shaped graphene / foam metal film is inverted and the substrate and glass substrate are separated by an ultraviolet small-size laser beam to obtain nanoparticle-shaped graphene / foam metal electrode raw material.

[0105] The prepared cyanate ester resin / copper foam composite film was placed on a worktable. The mid-infrared large-spot laser irradiation process employed a continuous CO2 laser (wavelength 10.6 μm) with a rated power of 50 W and a beam diameter of 250 μm. The laser power was set to 16 W, the defocusing distance to +2 mm, and a scanning speed of 100 mm / s and a scanning pixel step size of 1000 DPI. A grating-type S-shaped overlapping path (serpentine scanning) was used to perform laser direct writing scanning on the film. This scanning process in-situ grew nanoparticle-like graphene on the foam metal surface, inducing the cyanate ester resin / copper foam composite film to transform into a nanoparticle-like graphene / copper foam film. A schematic diagram of the surface microstructure of the nanoparticle-like graphene / foam metal film is shown below. Figure 5 As shown. Subsequently, the sample was placed upside down on the worktable. The ultraviolet small-size spot laser beam irradiation process used an ultraviolet picosecond pulsed laser with a center wavelength of 355nm, a repetition frequency of 600Hz, and a pulse width of about 10ps. The laser scanning adopted a left-to-right grating overlapping line-by-line path, with a scanning speed of 800mm / s, focusing, a scanning spacing of 25.4μm, and a laser power of 10.5W, in order to complete the substrate peeling process.

[0106] S3. Cut the nanoparticle-shaped graphene / foam metal electrode raw material obtained in step S2 into electrodes, clean and dry the electrodes, use laser ablation process to pattern the second mask, and attach the second mask to the electrode.

[0107] Nanoparticle-shaped graphene / foam metal electrode material was cut into 5mm × 6mm pieces to serve as electrodes. The electrode surfaces were then cleaned sequentially with anhydrous ethanol and deionized water, followed by drying at 50°C for 15 minutes. A second mask, made of polyimide with a thickness of 40μm, was used for high-precision patterning with a 355nm ultraviolet picosecond laser, set to a laser power of 16W, focusing, and a scanning speed of 60mm / s. After patterning, the polyimide portion corresponding to the electrolyte coating area was removed from the second mask using tweezers or a precision tool. The patterned second mask was then bonded to the electrode. During bonding, it was ensured that the inner edge of the second mask covered the electrode's working area, and the mask was repeatedly pressed with tweezers to thoroughly remove air bubbles. This operation aimed to ensure the reliability and sealing of the encapsulation structure.

[0108] S4. Take two electrodes obtained in step S3, and uniformly coat the surface of each electrode with ion gel electrolyte. Then transfer the electrodes to a vacuum chamber for vacuum treatment. After the ion gel electrolyte is transformed into a semi-solid state, align and attach several electrodes, apply pressure, and solidify and shape them at room temperature to obtain a sandwich-type filter supercapacitor.

[0109] The ionogel electrolyte is made of PVA / H2SO4 and is prepared as follows: Polyvinyl alcohol, deionized water, and H2SO4 are mixed at a mass ratio of 2.8g PVA:26g H2O:2.8g H2SO4, and stirred continuously at 90℃ for 2 hours to obtain the ionogel electrolyte. Subsequently, 0.2mL of the ionogel electrolyte is uniformly drop-coated onto the electrode surface and transferred to a vacuum chamber. After vacuum treatment at -0.8MPa, the sample is removed and placed in a 25℃ constant temperature drying oven for 12 hours to fully remove residual moisture.

[0110] like Figure 3 As shown, in this embodiment, each of the two electrodes has a working area coated with electrolyte. The working areas of the two electrodes are then precisely aligned and bonded together, and the electrodes are left to stand and fix at the same temperature (25°C) for 12 hours to obtain a single sandwich-type filter supercapacitor. The obtained supercapacitor exhibits a phase angle as high as -68.8° and a surface capacitance of 102.1 μF / cm² at 120 Hz. 2 (18 times that of commercial aluminum electrolytic capacitors), with a cutoff frequency of 2373Hz (10 times that of commercial aluminum electrolytic capacitors), an RC time constant of 0.40ms, and as... Figure 6 As shown, the CV curve remains quasi-rectangular at a scan rate of 2500 V / s. (Reference) Figure 9 Experimental tests have shown that it can filter various complex waveform signals and output a near-straight DC output signal with good filtering effect.

[0111] Example 2

[0112] S1. A substrate is bonded to a glass substrate, and then a foam metal with an open structure is placed on the substrate. The outer periphery of the foam metal is then fixed and sealed by applying pressure to the first mask with a single-sided adhesive coating. Liquid cyanate monomer is then coated on the foam metal and cured by constant temperature heating to obtain a cyanate resin / foam metal composite film.

[0113] A 125 μm thick polyimide film was cut into 50 mm × 50 mm segments and flatly attached to a 50 mm × 50 mm, 2 mm thick glass slide. The sample surface was then cleaned with anhydrous ethanol and rinsed with deionized water. After cleaning, it was dried in a 60 °C vacuum oven for 15 min to remove residual solvent and moisture. A 33 mm × 33 mm, 0.1 mm thick nickel foam was placed centered on the cleaned sample surface. A 100 μm thick square ring-shaped polyimide mask was used to position, fix, and seal the nickel foam area to ensure precise control of the area for subsequent operations. Simultaneously, the solid cyanate monomer was pretreated by heating it in a 70 °C water bath. After 30 minutes, the solid cyanate monomer transformed into a homogeneous liquid state for use. The sample assembly with the fixed nickel foam was placed on a balance tray. 0.3 g of liquid cyanate monomer was accurately weighed and slowly added dropwise to the nickel foam area. The monomer surface was then coated with a small stick to ensure uniform impregnation and complete coverage within the pores of the nickel foam. Finally, the assembly containing the sample was transferred to a preheated heating stage. A temperature program was set to progressively increase the sample temperature from an initial 90°C to 230°C over 8 hours for curing. The initial temperature was 90°C for 30 minutes to fully impregnate the metal foam pores; then, the temperature was increased to 120°C over 30 minutes and held for 30 minutes to activate the prepolymerization reaction and initiate bubble removal; the temperature was then increased to 150°C over 30 minutes and held for 30 minutes to complete dynamic venting; subsequently, the temperature was increased to 200°C over 30 minutes and held for 2 hours to control the main crosslinking exothermic peak; finally, the temperature was increased to 230°C over 30 minutes and held for 2 hours to strengthen the triazine ring network and ensure complete reaction. After the reaction, the sample was allowed to cool naturally to room temperature on the heating stage to obtain the target product—a cyanate ester resin / nickel foam composite film.

[0114] S2. The cyanate ester resin / foam metal composite film obtained in step S1 is irradiated with a mid-infrared large-size laser beam to generate a nanoparticle-shaped graphene / foam metal film; then the nanoparticle-shaped graphene / foam metal film is inverted and the substrate and glass substrate are separated by an ultraviolet small-size laser beam to obtain nanoparticle-shaped graphene / foam metal electrode raw material.

[0115] The prepared cyanate ester resin / nickel foam composite film was placed on a worktable. A continuous CO2 laser (wavelength 10.6 μm) with a rated power of 50 W and a beam diameter of 250 μm was used. The laser power was set to 16 W and the defocusing amount to +2 mm. A grating-type S-shaped overlapping path (serpentine scanning) was employed to perform laser direct writing scanning on the film at a scanning speed of 100 mm / s and a scanning pixel step size of 1000 DPI. This scanning process induced the in-situ growth of nanoparticle-like graphene on the foam metal surface, transforming the cyanate ester resin / nickel foam composite film into a nanoparticle-like graphene / nickel foam film. The XRD pattern of the nanoparticle-like graphene / nickel foam film is shown below. Figure 11 As shown, the Raman spectrum of the nanoparticle-shaped graphene / nickel foam film is as follows. Figure 12 As shown. Subsequently, the sample was placed upside down on the worktable, and an ultraviolet picosecond pulsed laser with a center wavelength of 355nm, a repetition frequency of 600Hz, and a pulse width of about 10ps was selected. The laser scanning adopted a left-to-right grating overlapping line-by-line path, with a scanning speed of 800mm / s, focusing, a scanning spacing of 25.4μm, and a laser power of 10.5W, in order to complete the substrate removal process.

[0116] S3. Cut the nanoparticle-shaped graphene / foam metal electrode raw material obtained in step S2 into electrodes, clean and dry the electrodes, use laser ablation process to pattern the second mask, and attach the second mask to the electrode.

[0117] Nanoparticle-shaped graphene / foam metal electrode material was cut into 5mm × 6mm pieces to serve as electrodes. The electrode surface was then cleaned sequentially with anhydrous ethanol and deionized water, followed by drying at 50°C for 15 minutes. Laser ablation was performed using a 355nm ultraviolet picosecond laser, with a laser power of 16W, focusing, and a scanning speed of 60mm / s. The second mask was patterned with high precision according to a pre-defined pattern. After processing, the polyimide portion corresponding to the electrolyte coating area on the second mask was removed using tweezers or a precision tool. Next, the patterned second mask was bonded to the electrode. During bonding, it was ensured that the inner edge of the second mask covered the electrode's working area, and the second mask was repeatedly pressed with tweezers to thoroughly remove air bubbles. This operation aimed to ensure the reliability and sealing of the encapsulation structure.

[0118] S4. Take the electrodes obtained in step S3, and uniformly coat the surface of each electrode with ion gel electrolyte. Then transfer the electrodes to a vacuum chamber for vacuum treatment. After the ion gel electrolyte is transformed into a semi-solid state, align and attach several electrodes, apply pressure, and solidify and shape them at room temperature to obtain a sandwich-type filter supercapacitor.

[0119] The ionogel electrolyte is made of PVA / H2SO4 and is prepared as follows: Polyvinyl alcohol, deionized water, and H2SO4 are mixed at a mass ratio of 2.8g PVA:26g H2O:2.8g H2SO4, and stirred continuously at 90℃ for 2 hours to obtain the ionogel electrolyte. Subsequently, 0.2mL of the ionogel electrolyte is uniformly drop-coated onto the electrode surface and transferred to a vacuum chamber. After vacuum treatment at -0.8MPa, the sample is removed and placed in a 25℃ constant temperature drying oven for 12 hours to fully remove residual moisture.

[0120] like Figure 4 As shown, in this embodiment, the first and last electrodes each have an electrolyte-coated working area, and the nine electrodes in the middle each have two electrolyte-coated working areas. The electrolyte-coated surface of each electrode is then precisely aligned and bonded to its adjacent electrode. Each electrode in the middle is staggered from its two adjacent electrodes and arranged in series. After being statically fixed for 12 hours in a uniform temperature environment (25°C), a sandwich-type filter supercapacitor with a series array is obtained. The resulting supercapacitor exhibits a phase angle as high as -70° at 120Hz and a surface capacitance of 245μF / cm². 2 (44 times that of commercial aluminum electrolytic capacitors), such as Figure 8 As shown, the cutoff frequency is as high as 3020Hz (12 times that of commercial aluminum electrolytic capacitors), and the RC time constant is as low as 0.33ms. The fabricated series array sandwich-type filter supercapacitor has a linear operating voltage extension to 10V, such as... Figure 7 As shown, the CV curve shows no distortion at a scan rate of 5000V / s. (Reference) Figure 10 In actual filtering tests, the variance coefficient of the output DC signal for complex waveforms such as sine waves and pulse waves is less than 0.00024, indicating good filtering performance.

[0121] Other configurations and operations according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0122] In the description of this specification, references to terms such as "embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0123] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for fabricating a supercapacitor based on nanoparticle-like graphene / foam metal, characterized in that, Includes the following steps: S1. A substrate is bonded to a glass substrate, and then a foam metal with an open structure is placed on the substrate. The outer periphery of the foam metal is then fixed and sealed by applying pressure to the first mask with a single-sided adhesive coating. Liquid cyanate monomer is then coated on the foam metal and cured by constant temperature heating to obtain a cyanate resin / foam metal composite film. S2. The cyanate ester resin / foam metal composite film obtained in step S1 is irradiated with a mid-infrared large-size laser beam to generate a nanoparticle-shaped graphene / foam metal film; then the nanoparticle-shaped graphene / foam metal film is inverted and the substrate and glass substrate are separated by an ultraviolet small-size laser beam to obtain nanoparticle-shaped graphene / foam metal electrode raw material. S3. Cut the nanoparticle-shaped graphene / foam metal electrode raw material obtained in step S2 into electrodes, clean and dry the electrodes, use laser ablation process to pattern the second mask, and attach the second mask to the electrode. S4. Take at least two electrodes obtained in step S3, uniformly coat the surface of each electrode with ion gel electrolyte, and then transfer the electrodes to a vacuum chamber for vacuum treatment; after the ion gel electrolyte is transformed into a semi-solid state, align and attach several electrodes, apply pressure, and solidify and shape them at room temperature to obtain a sandwich-type filter supercapacitor.

2. The method for preparing a supercapacitor based on nanoparticle-like graphene / foam metal according to claim 1, characterized in that: In step S1, the substrate is made of polyimide or polyethylene terephthalate, and the thickness of the substrate is 0.01 mm to 0.2 mm.

3. The method for preparing a supercapacitor based on nanoparticle-shaped graphene / foam metal according to claim 1, characterized in that: In step S1, the foam metal is foam nickel or foam copper, and the thickness of the foam metal is 0.1 mm to 0.3 mm.

4. The method for preparing a supercapacitor based on nanoparticle-like graphene / foam metal according to claim 1, characterized in that: In steps S1 and S2, the first mask and the second mask are both made of polyimide or polyethylene terephthalate, and both have a thickness of 20 to 125 μm.

5. The method for preparing a supercapacitor based on nanoparticle-like graphene / foam metal according to claim 1, characterized in that: It also includes pretreating solid cyanate monomers into liquid cyanate monomers, placing the solid cyanate in a container, sealing the container, and then immersing the container in a water bath for heating at a temperature of 50-70°C for 20-30 minutes.

6. The method for preparing a supercapacitor based on nanoparticle-like graphene / foam metal according to claim 1, characterized in that: Liquid cyanate monomer is added dropwise in a proportional manner, with the addition amount of liquid cyanate monomer relative to the unit area of ​​the foamed metal being 20 mg / cm². 2 Up to 50 mg / cm 2 .

7. The method for preparing a supercapacitor based on nanoparticle-like graphene / foam metal according to claim 1, characterized in that: In step S1, the heating and curing process adopts a stepped heating method, with a heating temperature of 90-230℃ and a time of 7-8 hours.

8. The method for preparing a supercapacitor based on nanoparticle-like graphene / foam metal according to claim 1, characterized in that: In step S2, the spot size of the mid-infrared large-size laser beam is 200-500μm, the scanning adopts a grating-type S-shaped overlapping path (serpentine scanning), the scanning speed is 80-120mm / s, the defocusing amount is +2-+4mm, the scanning pixel step size is 800-1200DPI, and the laser power is 7.5-25W.

9. The method for preparing a supercapacitor based on nanoparticle-like graphene / foam metal according to claim 1, characterized in that: In step S2, the spot size of the ultraviolet small-size laser beam is 10μm to 20μm, the pulse center wavelength is 355nm, the pulse width is 5 to 20ps, the scanning adopts a left-to-right grating overlapping line-by-line path, the scanning speed is 600 to 1000mm / s, focusing is performed, the scanning interval is 15 to 25.4μm, and the laser power is set to 7.5 to 16W.

10. A filtering supercapacitor, characterized in that, Prepared using the preparation method according to any one of claims 1-9.

Images