Bi-crosslinking reduced graphene oxide film material as well as preparation method and application thereof
Reduced graphene oxide films were prepared by synergistic crosslinking of aminotrimethylene phosphonic acid and 4,4'-diaminobiphenyl, which solved the problems of insufficient graphene sheet stacking and active sites, and improved the electrochemical performance of flexible supercapacitors.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-03
- Publication Date
- 2026-04-14
AI Technical Summary
Existing reduced graphene oxide materials in flexible supercapacitors suffer from problems such as easy stacking of graphene sheets and a limited number of active sites, which limits their electrochemical performance.
Reduced graphene oxide films were prepared by synergistic crosslinking of aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl. A stable composite structure was formed through solvothermal reaction, which prevented graphene sheet stacking and increased active sites.
It increases the ion accessibility area and the number of active sites, enhancing the electrochemical performance of the electrode material and making it suitable for flexible supercapacitors.
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Figure CN121849928A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of supercapacitor electrode material technology, specifically relating to a double-crosslinked reduced graphene oxide thin film material, its preparation method, and its application. Background Technology
[0002] With the rapid development of industrialization and informatization, people's demands for electronic devices are gradually moving towards lightweight, portable, and flexible designs. This requires that the energy storage systems of electronic devices not only have high energy storage capacity but also light weight, high flexibility, and mechanical strength. Flexible supercapacitors, as a new type of flexible energy storage device, have become one of the most promising flexible power sources due to their advantages of high power density, good cycle stability, high safety and reliability, as well as unique mechanical deformation capabilities.
[0003] Reduced graphene oxide (RGO)-based anode materials are considered highly promising flexible electrodes for supercapacitors due to their excellent conductivity, large specific surface area, chemical stability, and corrosion resistance. In particular, the oxygen-containing functional groups on the RGO surface can serve as active sites to enhance ion storage capacity and as sites for grafting organic, inorganic, and nanoparticles into chemical reactions. However, single-layer reduced graphene oxide has significant drawbacks in practical applications. For example, graphene sheets tend to stack, reducing the effective ion access area and thus affecting electrochemical performance. Furthermore, the limited number of active sites in reduced graphene oxide itself also limits its ion storage capacity.
[0004] To address these issues, researchers have proposed various modification strategies. However, most RGO electrodes prepared using existing modification methods require traditional coating processes, which are unsuitable for flexible supercapacitors. Furthermore, the degree of crosslinking modification of RGO in the prepared electrodes is insufficient, limiting the improvement of the capacitor's electrochemical performance and restricting its further application.
[0005] Therefore, how to develop an electrode material for a flexible supercapacitor and further improve its electrochemical performance is the technical problem to be solved by this invention. Summary of the Invention
[0006] To address the shortcomings of the existing technology, the present invention aims to provide a double-crosslinked reduced graphene oxide thin film material, its preparation method, and its applications. The present invention utilizes aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl for synergistic crosslinking to prepare a reduced graphene oxide thin film, which can alleviate the self-stacking phenomenon of the reduced graphene oxide thin film, improve the electrochemical storage capacity of the composite film, and greatly meet the application requirements of supercapacitor electrode materials.
[0007] To achieve the above objectives, the first aspect of the present invention adopts the following technical solution: A method for preparing a double-crosslinked reduced graphene oxide thin film material includes the following steps: (1) The graphene oxide dispersion was mixed with aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl to obtain a mixed dispersion; the mass ratio of aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl was (0.3~1.0):(0.2~2); (2) The mixed dispersion is reacted at 60~80℃, and the product obtained from the reaction is dried to obtain the film precursor; (3) The film precursor is subjected to a solvothermal reaction in a solvent and then cooled to obtain the double crosslinked reduced graphene oxide film material.
[0008] In a preferred embodiment, in step (1), the concentration of graphene oxide in the graphene oxide dispersion is 1~3 mg / mL, more preferably 2 mg / mL. For ease of addition and to promote uniform dispersion of graphene oxide, in practice, a graphene oxide solution can be directly obtained, and then added to deionized water for ultrasonic dispersion, thereby preparing the graphene oxide dispersion.
[0009] As a preferred embodiment, in step (1), the process of uniformly mixing the graphene oxide dispersion with aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl is as follows: first, aminotrimethylenephosphonic acid is added to the graphene oxide dispersion and stirred and mixed, and then 4,4'-diaminobiphenyl is added and stirred and mixed; the stirring speed is 100~400 r / min and the time is 20~100 min.
[0010] Aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl act as both crosslinking agents and blocking agents, and their dosage and addition method have different effects on the morphology and structure of the product. Furthermore, the dosages of aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl need to be matched with the dosage of graphene oxide. In a preferred embodiment, in step (1), the mass ratio of graphene oxide to aminotrimethylenephosphonic acid in the graphene oxide dispersion is (25~35):(0.3~1.0).
[0011] To further optimize the structure of the composite material and improve its electrochemical performance, as a preferred embodiment, the mass ratio of graphene oxide, aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl in the graphene oxide dispersion is 10:0.1:0.1.
[0012] Based on the consideration of promoting the structural stability of the thin film precursor, as a preferred embodiment, the reaction time in step (2) is 60~100min.
[0013] In step (2), the water content in the reaction product is fully removed by drying, thereby preparing the film precursor by self-stacking. In a preferred embodiment, the drying temperature in step (2) is 60~100℃ and the drying time is 4~10h. More preferably, the drying temperature is 80℃ and the drying time is 6h.
[0014] In a preferred embodiment, in step (3), the solvent is one or more of anhydrous ethanol, methanol, and ethylene glycol, more preferably anhydrous ethanol.
[0015] In step (3), a solvothermal reaction is carried out to partially reduce the graphene oxide in the precursor and optimize the structure of the resulting composite film. In order to ensure the electrochemical performance of the film material while taking into account the thermal treatment efficiency and cost, as a preferred embodiment, the temperature of the solvothermal reaction is 60~100℃ and the time is 250~450min.
[0016] The second aspect of the present invention adopts the following technical solution: A double-crosslinked reduced graphene oxide thin film material prepared by the preparation method described above.
[0017] The third aspect of this invention adopts the following technical solution: An application of the double-crosslinked reduced graphene oxide thin film material as described above, wherein the application is the use of the double-crosslinked reduced graphene oxide thin film material as an electrode material for a supercapacitor; the electrode material is a negative electrode material.
[0018] The technical solution of the present invention has the following beneficial effects: The present invention discloses a method for preparing a double-crosslinked reduced graphene oxide film material, which uses graphene oxide, aminotrimethylene phosphonic acid, and 4,4'-diaminobiphenyl as raw materials, and obtains a reduced graphene oxide composite film with synergistic crosslinking of aminotrimethylene phosphonic acid and 4,4'-diaminobiphenyl through a simple and efficient two-step heat treatment.
[0019] The preparation process of this invention is simple and the synthesis conditions are mild, making it suitable for large-scale mass production and showing good prospects for industrial applications. Furthermore, the reduced graphene oxide film material prepared by this invention is a self-supporting structure film material that can be used directly without coating, avoiding the use of electronically insulating binders and inactive conductive additives and current collectors. This effectively improves the specific capacity and ion storage capacity of the electrode, making it suitable as a flexible electrode for use in supercapacitors.
[0020] In particular, this invention uses aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl as both barrier agents and crosslinking agents to modify graphene, forming a stable composite structure. This not only helps prevent the stacking of graphene sheets and increases the ion access area, but also increases the number of active sites and enhances ion storage capacity, thereby synergistically improving the electrochemical performance of the material. It has outstanding application prospects in the preparation and application of electrode materials for supercapacitors. Attached Figure Description
[0021] Figure 1 The XRD patterns are of the reduced graphene oxide thin film materials prepared in Example 2 and Comparative Example 3 of this invention. Figure 2 The cyclic voltammetry curves of the reduced graphene oxide thin film materials in Examples 1-3 of this invention are shown below. Figure 3 The constant current charge-discharge curves of the reduced graphene oxide thin film materials in Examples 1-2 of this invention are shown. Figure 4 The specific capacity of the reduced graphene oxide thin film material of Example 2 of the present invention at different current densities; Figure 5 The cyclic voltammetry curves of the reduced graphene oxide thin film materials in Examples 2 and 4 of this invention are shown below. Figure 6 The constant current charge-discharge curves of the reduced graphene oxide thin film materials in Examples 2 and 4 of this invention are shown. Figure 7 The constant current charge-discharge curves of the reduced graphene oxide thin film materials of Example 2 and Comparative Examples 1-3 of the present invention are shown. Detailed Implementation
[0022] The technical solution and technical effects of the present invention will be further described below with reference to specific embodiments and accompanying drawings. The following description is for illustrative purposes only and should not be construed as limiting the scope of protection of the present invention. Unless otherwise specified, the methods used in the following embodiments are conventional methods in the art. Unless otherwise specified, the raw materials or reagents used in the following embodiments are conventional commercially available materials in the art.
[0023] In the following examples, the graphene oxide used can be obtained through commercial channels or prepared by referring to existing technologies using the Hummer's method. Specifically, the graphene oxide used below is a graphene oxide solution prepared by Hummer's method. The specific preparation method includes the following steps: a) Weigh 2.0 g of graphite and 4.0 g of sodium nitrate and add them to 60 mL of concentrated sulfuric acid. Stir evenly in an ice-water bath to obtain a mixed solution; b) Slowly add 6.0 g of potassium permanganate solid to the above mixed solution to obtain a dark green mixed solution; c) After the potassium permanganate is added, stir the dark green mixed solution in a 35 °C water bath for 3 h, and then add 200 mL of H2O dropwise; d) After the H2O is added, place the resulting mixture in a 90 °C water bath for 2 h; e) After the reaction is completed, pour in 25 mL of H2O2. At this time, the color of the mixture turns golden yellow; f) Finally, wash with 2 mol / L hydrochloric acid, and then dialyze. When the graphene oxide solution is weakly acidic, determine its concentration by differential method to obtain a graphene oxide (GO) solution with a concentration of 6 mg / mL.
[0024] Example 1
[0025] This embodiment provides a double-crosslinked reduced graphene oxide thin film material, the preparation method of which includes the following steps: (1) Mix 5 mL of graphene oxide solution (6 mg / mL) with 10 mL of deionized water and ultrasonically disperse for 30 min to obtain a graphene oxide dispersion with a concentration of 2 mg / mL. (2) Add 1 mg of aminotrimethylenephosphonic acid to the graphene oxide dispersion obtained in step (1), stir magnetically at 200 r / min for 30 min, then add 0.2 mg of 4,4'-diaminobiphenyl, stir magnetically at 200 r / min for 60 min to obtain a mixed dispersion; (3) The mixed dispersion obtained in step (2) was placed in an oil bath at 70°C and reacted for 80 min. Then the product obtained from the reaction was transferred to a petri dish and dried in an oven at 80°C for 6 h to obtain the film precursor. (4) The film precursor obtained in step (3) was subjected to a solvothermal reaction in 25 mL of anhydrous ethanol at a temperature of 80 °C for 360 min. After the reaction, the film was cooled to obtain the double crosslinked reduced graphene oxide film material of this embodiment.
[0026] Example 2
[0027] This embodiment provides a double-crosslinked reduced graphene oxide thin film material, the preparation method of which includes the following steps: (1) Mix 5 mL of graphene oxide solution (6 mg / mL) with 10 mL of deionized water and ultrasonically disperse for 30 min to obtain a graphene oxide dispersion with a concentration of 2 mg / mL. (2) Add 0.3 mg of aminotrimethylenephosphonic acid to the graphene oxide dispersion obtained in step (1), stir magnetically at 200 r / min for 30 min, then add 0.3 mg of 4,4'-diaminobiphenyl, stir magnetically at 200 r / min for 60 min to obtain a mixed dispersion; (3) The mixed dispersion obtained in step (2) was placed in an oil bath at 70°C and reacted for 80 min. Then the product obtained from the reaction was transferred to a petri dish and dried in an oven at 80°C for 6 h to obtain the film precursor. (4) The film precursor obtained in step (3) was subjected to a solvothermal reaction in 25 mL of anhydrous ethanol at a temperature of 80 °C for 360 min. After the reaction, the film was cooled to obtain the double crosslinked reduced graphene oxide film material of this embodiment.
[0028] Example 3
[0029] This embodiment provides a double-crosslinked reduced graphene oxide thin film material, the preparation method of which includes the following steps: (1) Mix 5 mL of graphene oxide solution (6 mg / mL) with 10 mL of deionized water and ultrasonically disperse for 30 min to obtain a graphene oxide dispersion with a concentration of 2 mg / mL. (2) Add 0.4 mg of aminotrimethylenephosphonic acid to the graphene oxide dispersion obtained in step (1), stir magnetically at 200 r / min for 30 min, then add 2.0 mg of 4,4'-diaminobiphenyl, stir magnetically at 200 r / min for 60 min to obtain a mixed dispersion; (3) The mixed dispersion obtained in step (2) was placed in an oil bath at 70°C and reacted for 80 min. Then the product obtained from the reaction was transferred to a petri dish and dried in an oven at 80°C for 6 h to obtain the film precursor. (4) The film precursor obtained in step (3) was subjected to a solvothermal reaction in 25 mL of anhydrous ethanol at a temperature of 80 °C for 360 min. After the reaction, the film was cooled to obtain the double crosslinked reduced graphene oxide film material of this embodiment.
[0030] Example 4
[0031] This embodiment provides a double-crosslinked reduced graphene oxide thin film material, the preparation method of which includes the following steps: (1) Mix 5 mL of graphene oxide solution (6 mg / mL) with 10 mL of deionized water and ultrasonically disperse for 30 min to obtain a graphene oxide dispersion with a concentration of 2 mg / mL. (2) Add 0.3 mg of aminotrimethylenephosphonic acid to the graphene oxide dispersion obtained in step (1), stir magnetically at 200 r / min for 30 min, then add 0.3 mg of 4,4'-diaminobiphenyl, stir magnetically at 200 r / min for 60 min to obtain a mixed dispersion; (3) The mixed dispersion obtained in step (2) was placed in an oil bath at 70°C and reacted for 80 min. Then the product obtained from the reaction was transferred to a petri dish and dried in an oven at 80°C for 6 h to obtain the film precursor. (4) The film precursor obtained in step (3) was subjected to a solvothermal reaction in 25 mL of anhydrous ethanol at a temperature of 100 °C for 360 min. After the reaction, the film was cooled to obtain the double crosslinked reduced graphene oxide film material of this embodiment.
[0032] Comparative Example 1 This comparative example provides a reduced graphene oxide film material, the preparation method of which is similar to that of Example 2. The difference is that in step (2) of this comparative example, aminotrimethylenephosphonic acid is omitted and replaced with an equal mass of 4,4'-diaminobiphenyl.
[0033] Specifically, step (2) of the comparative example was adjusted as follows: 0.3 mg of 4,4'-diaminobiphenyl was added to the graphene oxide dispersion obtained in step (1), and the mixture was magnetically stirred at 200 r / min for 30 min. Then, another 0.3 mg of 4,4'-diaminobiphenyl was added, and the mixture was magnetically stirred at 200 r / min for 60 min to obtain a mixed dispersion. The other steps were the same as in Example 2, and the reduced graphene oxide film material of this comparative example was prepared.
[0034] Comparative Example 2 This comparative example provides a reduced graphene oxide film material, the preparation method of which is similar to that of Example 2. The difference is that in step (2) of this comparative example, 4,4'-diaminobiphenyl is omitted and replaced with an equal mass of aminotrimethylenephosphonic acid.
[0035] Specifically, step (2) of the comparative example was adjusted as follows: 0.3 mg of aminotrimethylenephosphonic acid was added to the graphene oxide dispersion obtained in step (1), and the mixture was magnetically stirred at 200 r / min for 30 min. Then, another 0.3 mg of aminotrimethylenephosphonic acid was added, and the mixture was magnetically stirred at 200 r / min for 60 min to obtain a mixed dispersion. The other steps were the same as in Example 2, and the reduced graphene oxide film material of the comparative example was prepared.
[0036] Comparative Example 3 This comparative example provides a reduced graphene oxide film material, the preparation method of which is similar to that of Example 2. The difference is that in step (2) of this comparative example, 4,4'-diaminobiphenyl and aminotrimethylenephosphonic acid are omitted and replaced with equal mass of deionized water.
[0037] Specifically, step (2) of the comparative example was adjusted as follows: 0.3 mg of deionized water was added to the graphene oxide dispersion obtained in step (1), and the mixture was magnetically stirred at 200 r / min for 30 min. Then, another 0.3 mg of deionized water was added, and the mixture was magnetically stirred at 200 r / min for 60 min to obtain a mixed dispersion. The other steps were the same as in Example 2, and the reduced graphene oxide film material of the comparative example was prepared.
[0038] Experimental Example 1: XRD Analysis In this experimental example, X-ray diffraction (XRD) was used to analyze the reduced graphene oxide film materials prepared in Example 2 and Comparative Example 3. The scanning angle was 10–80°, and the obtained XRD patterns are shown below. Figure 1 As shown.
[0039] Figure 1 The XRD pattern shows that, compared with Comparative Example 3, the thin film sample prepared in Example 2 of the present invention has a stronger characteristic peak of graphene oxide at 2θ of 11°, which proves that the graphene oxide was not completely reduced. The characteristic peak of carbon (002) crystal plane appears at around 22°, and no other peaks appear, which proves that the sample synthesized in the present invention is a pure phase of reduced graphene oxide thin film synergistically crosslinked with aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl.
[0040] Experimental Example 2: Electrochemical Performance Testing To test the performance of the thin film samples prepared in this invention as a negative electrode material for supercapacitors, a three-electrode system was assembled to evaluate the electrochemical performance of the materials. Specifically, the methods and parameters for measuring electrochemical performance were as follows: a platinum sheet electrode was used as the counter electrode, a saturated calomel electrode as the reference electrode, and the thin film materials of Examples 1-4 and Comparative Examples 1-3 were used as the working electrodes. The electrolyte was a 6.0M KOH solution. The galvanostatic charge-discharge (GCD) and cyclic voltammetry (CV) performance tests were performed on a Shanghai Chenhua CHI660E electrochemical workstation. The voltage window for GCD was -1.0V to 0V, the current density was 1A / g, and the scan rate for CV was 20mV / s, with a voltage window range of -1.0V to 0V.
[0041] Figure 2 The cyclic voltammetry curves are for the thin film materials in Examples 1-3. Figure 3 The constant current charge-discharge curves are for the thin film materials in Examples 1 and 2. Figure 4The specific capacity results of the thin film material in Example 2 under different current densities are shown. Figure 5 The cyclic voltammetry curves are for the thin film materials of Examples 2 and 4. Figure 6 The constant current charge-discharge curves are for the thin film materials of Examples 2 and 4. Figure 7 The constant current charge-discharge curves are for the thin film materials of Example 2 and Comparative Examples 1-3.
[0042] Depend on Figure 2 It is observed that as the ratio of aminotrimethylenephosphonic acid to 4,4'-diaminobiphenyl gradually decreases (from 5:1 to 1:5 in Examples 1-3), the area enclosed by the cyclic voltammetry curve at a scan rate of 20 mV / s first increases and then decreases. This is mainly because excessive aminotrimethylenephosphonic acid affects the electronic conductivity of the material, thus preventing some oxygen functional groups from storing ions. With decreasing aminotrimethylenephosphonic acid and increasing 4,4'-diaminobiphenyl, the capacity gradually increases; however, excessive 4,4'-diaminobiphenyl is also detrimental to capacity performance. Therefore, it is necessary to rationally control the ratio of aminotrimethylenephosphonic acid to 4,4'-diaminobiphenyl.
[0043] Depend on Figure 3 As can be seen, at a current density of 1 A / g, comparing the galvanostatic charge-discharge curves of the two samples clearly shows that Example 2 exhibits a higher specific capacity, while the Sample 1 shows a significant tailing at the low potential (-1.1 V), which is attributed to its poor conductivity. This is consistent with... Figure 2 The information conveyed is consistent.
[0044] Depend on Figure 4 As can be seen from the GCD curve, as the current density increases from 1 A / g to 5 A / g, the capacity retention of the sample in Example 2 can reach 83%, which also indicates that the sample has high electronic and ionic conductivity.
[0045] Depend on Figures 5-6 It can be seen that, under the same scanning speed and the same current density, as the reduction temperature of graphene oxide increases from 80 to 100℃, the area enclosed by CV decreases, the GCD discharge time shortens, and the storage capacity decreases. This is mainly because the excessively high reduction temperature reduces the oxygen content, thereby reducing the number of active sites and causing capacity decay.
[0046] Depend on Figure 7 It is evident that without the addition of aminotrimethylenephosphonic acid or 4,4'-diaminobiphenyl during the material preparation process, the synthesized thin film material samples exhibited lower CV curve area and specific capacitance in the supercapacitor test at a constant current charge-discharge curve of 1 A / g. This indicates that the electrochemical performance of the thin film materials in Comparative Examples 1-3 is inferior to that of the thin film material of this invention, mainly due to poor conductivity and insufficient active sites.
[0047] In summary, this invention uses aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl as both barrier agents and crosslinking agents to modify graphene. This not only effectively prevents the stacking of graphene sheets and increases the ion access area, but also increases the number of active sites and enhances ion storage capacity, thereby synergistically improving the electrochemical performance of the material. It has high practical application value in the field of supercapacitors.
[0048] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.
Claims
1. A method for preparing a double-crosslinked reduced graphene oxide thin film material, characterized in that, Includes the following steps: (1) The graphene oxide dispersion was mixed with aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl to obtain a mixed dispersion; the mass ratio of aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl was (0.3~1.0):(0.2~2); (2) The mixed dispersion is reacted at 60~80℃, and the product obtained from the reaction is dried to obtain the film precursor; (3) The film precursor is subjected to a solvothermal reaction in a solvent and then cooled to obtain the double crosslinked reduced graphene oxide film material.
2. The method for preparing the double-crosslinked reduced graphene oxide thin film material according to claim 1, characterized in that, In step (1), the concentration of the graphene oxide dispersion is 1~3 mg / mL.
3. The method for preparing the double-crosslinked reduced graphene oxide thin film material according to claim 1, characterized in that, In step (1), the process of uniformly mixing the graphene oxide dispersion with aminotrimethylenephosphonic acid and 4,4'-diaminobiphenyl is as follows: first, aminotrimethylenephosphonic acid is added to the graphene oxide dispersion and stirred and mixed, and then 4,4'-diaminobiphenyl is added and stirred and mixed; the stirring speed is 100~400 r / min and the time is 20~100 min.
4. The method for preparing the double-crosslinked reduced graphene oxide thin film material according to claim 1, characterized in that, In step (1), the mass ratio of graphene oxide to aminotrimethylenephosphonic acid in the graphene oxide dispersion is (25~35):(0.3~1.0).
5. The method for preparing the double-crosslinked reduced graphene oxide thin film material according to any one of claims 1 to 4, characterized in that, In step (2), the reaction time is 60~100 min.
6. The method for preparing the double-crosslinked reduced graphene oxide thin film material according to any one of claims 1 to 4, characterized in that, In step (2), the drying temperature is 60~100℃ and the time is 4~10h.
7. The method for preparing the double-crosslinked reduced graphene oxide thin film material according to any one of claims 1 to 4, characterized in that, In step (3), the solvent is one or more of anhydrous ethanol, methanol, and ethylene glycol.
8. The method for preparing the double-crosslinked reduced graphene oxide thin film material according to any one of claims 1 to 4, characterized in that, In step (3), the temperature of the solvothermal reaction is 60~100℃ and the time is 250~450min.
9. A double-crosslinked reduced graphene oxide thin film material prepared by the preparation method according to any one of claims 1 to 8.
10. An application of the double-crosslinked reduced graphene oxide thin film material as described in claim 9, characterized in that, The application is the use of double-crosslinked reduced graphene oxide thin film material as an electrode material for supercapacitors; the electrode material is a negative electrode material.