N-type conductive polymer-based supercapacitor and preparation method thereof
By using hydroquinone and its derivatives along with neutral salts as electrolytes in n-type conductive polymer supercapacitors, the problems of low electrochemical stability and low doping efficiency have been solved, resulting in supercapacitors with high specific capacitance and long cycle life, thus advancing the practical application of high energy density energy storage devices.
Patent Information
- Application Number
- CN202511069647.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-31
- Publication Date
- 2025-11-18
AI Technical Summary
Existing n-type conductive polymer supercapacitors suffer from bottlenecks in electrochemical stability, doping efficiency, and stringent synthesis conditions, resulting in poor performance in terms of high energy density and cycle stability.
Hydroquinone and its derivatives, along with neutral salt, are used as electrolytes and combined with poly(benzodifurandione) materials. By adding hydroquinone and its derivatives to the neutral salt electrolyte, the conductivity and stability of the electrode are enhanced, and the contribution of pseudocapacitance is increased.
The specific capacitance and cycle life of the n-type conductive polymer supercapacitor have been significantly improved. The device retains more than 92% of its capacity after 50,000 cycles, breaking through the traditional bottleneck and demonstrating the broad prospects of high-performance organic energy storage devices.
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Figure CN120977781A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of capacitors, in particular to an n-type conductive polymer-based supercapacitor and a preparation method thereof. BACKGROUND
[0002] Supercapacitors (also known as electrochemical capacitors) are a kind of energy storage devices that combine the high power characteristics of traditional capacitors and the high energy density characteristics of secondary batteries, and mainly rely on the charge storage mechanism at the electrode / electrolyte interface for energy storage. According to its energy storage mechanism, supercapacitors can be divided into electrochemical double-layer capacitors (EDLC) based on ion physical adsorption and pseudo-capacitors based on fast reversible redox reactions. Compared with lithium-ion batteries, supercapacitors have the advantages of high power density (up to 10 kW·kg -1 ), fast charging and discharging capability (can be completed in seconds), excellent cycle life (cycle times can reach 10 4 ~ 10 6 times), etc. Therefore, they show broad application prospects and market value in the fields of electric vehicle start-stop systems, rail transit energy recovery, wind-solar storage combined systems, smart grid frequency modulation and peak shaving, etc.
[0003] However, the energy density of current commercial supercapacitors is much lower than that of lithium batteries, which is one of the key bottlenecks limiting their further replacement of chemical batteries. In-depth analysis shows that the improvement of energy density is subject to the charge storage capacity of the electrode material, which is the core component. Although traditional carbon-based materials (such as activated carbon, carbon nanotubes, graphene) have excellent electrical conductivity and specific surface area, their main energy storage mode is physical adsorption, which lacks the contribution of pseudo-capacitance, resulting in generally low specific capacitance. While transition metal oxides (such as RuO2, MnO2, NiCo2O4, etc.) have high pseudo-capacitance, they have problems such as high cost, complex synthesis, high environmental toxicity, and poor cycle stability, which are difficult to support large-scale industrialization.
[0004] In recent years, conductive polymers are expected to be used as electrode materials for supercapacitors to solve the energy density bottleneck due to their adjustable π-conjugated structure, fast redox reaction ability, high pseudo-capacitance capacity, and good flexible processing performance. Among them, p-type conductive polymers such as polyaniline (PANI), polypyrrole (PPy), and poly(3,4-ethylenedioxythiophene) (PEDOT) have been widely studied and applied. The main chain of this type of material carries a positive charge, and the oxidation state / reduction state of the main chain can be switched to realize the embedding / extraction process of anions, complete the storage and release of energy. However, due to the low conductivity of the material itself, most p-type polymers still need to be compounded with conductive carbon, carbon nanotubes, and other materials in practical applications. In the charging and discharging process, the composite electrode is prone to volume change, electrode structure powdering, and reduced cycle life. In addition, due to the limitation of the working potential of single p-type conductive polymer, it is necessary to form a matching asymmetric capacitor device structure with n-type materials to widen the voltage window and realize high-energy density supercapacitors.
[0005] N-type conductive polymers can be used to construct single symmetric supercapacitor devices or to construct wide voltage window and high energy density supercapacitors by matching with p-type materials due to their reduced-state electronic conductivity. However, the practical application of n-type conductive polymers has long faced the following three key technical problems: (1) poor electrochemical stability: under the working potential, the main chain with negative charge (reduced doped state) structure is easily eroded by water or oxygen in the environment / electrolyte, leading to main chain carrier quenching, reduced conductivity, and supercapacitor performance degradation or even inactivation; (2) low doping efficiency of most n-type conductive polymers: n-type doping usually relies on electron donors or strong reducing molecules, but these dopants may form energy barriers at the electrode interface, increase the interface impedance, and have low doping efficiency, resulting in poor conductivity of most n-type conductive polymers, which makes it difficult to use as an electrode and still requires the addition of additional conductive substances; (3) harsh synthesis and processing conditions: the preparation of traditional n-type polymers requires an inert atmosphere, water-free and oxygen-free environment, which increases the cost and is not conducive to large-scale production and flexible device integration.
[0006] Therefore, it is necessary to further optimize n-type conductive polymer-based supercapacitors to promote their practical application in high-performance energy storage devices. SUMMARY
[0007] In order to solve the problems of low capacitance and poor cycle stability of n-type conductive polymer poly(benzodifuran-dione) (PBFDO) in supercapacitor applications, the application provides an n-type conductive polymer-based supercapacitor and a preparation method thereof. The specific method is: by additionally adding hydroquinone and its derivatives in a neutral salt electrolyte. The introduction of hydroquinone and its derivatives can not only significantly improve the pseudo-capacitance contribution of the system through its reversible oxidation and reduction, but also enhance the electrode conductivity stability and improve the cycle life through the intermolecular interaction between PBFDO. Experimental results show that under the condition of 20mM HQ concentration, the specific capacitance of the PBFDO device is increased by nearly 75%, and the capacity is still maintained at more than 92% after 50,000 cycles. This strategy breaks the traditional bottleneck of n-type conductive polymers in energy density and electrochemical stability, and shows the broad prospects of realizing high-performance organic energy storage devices through the synergistic design of materials and electrolytes.
[0008] Therefore, it is necessary to provide an n-type conductive polymer-based supercapacitor, which comprises the following structures in sequence: a positive electrode, an electrolyte layer and a negative electrode.
[0009] The structure of the positive electrode and the negative electrode is a poly(benzodifuran-dione) (PBFDO) layer and a current collector layer.
[0010] The electrolyte layer comprises a water-based separator and an electrolyte infiltrated in the water-based separator, and the material of the electrolyte is selected from one or more of a neutral salt and hydroquinone and its derivatives.
[0011] Further, the neutral salt is selected from one or more of sodium chloride, potassium chloride and lithium chloride.
[0012] Further, the structure of the hydroquinone and its derivatives is as follows:
[0013]
[0014] The R is selected from one or more of hydrogen, alkyl, alkyl derivative, sulfonate, carboxyl and hydroxyl.
[0015] One or more carbons on the alkyl derivative are substituted by one or more of oxygen atoms, sulfone groups, sulfoxide groups, carbonyl groups, aryl groups, olefin groups, alkyne groups, ester groups, cyano groups and nitro groups.
[0016] Further, the material of the current collector layer is selected from one or more of carbon paper, carbon cloth, graphite, copper foil and foamed nickel.
[0017] Further, the material of the water-based separator is one or more of cellulose paper, polypropylene and PAN / PVDF-HFP.
[0018] The application further provides a preparation method of the n-type conductive polymer-based supercapacitor, comprising the following steps:
[0019] S1, dropping a poly(benzodifuran-dione) solution on a current collector to obtain a positive electrode and a negative electrode respectively;
[0020] S2, placing a water-based separator on the positive electrode, and then coating an electrolyte solution, so that the electrolyte completely infiltrates the water-based separator to form an electrolyte layer;
[0021] S3, placing the negative electrode on the side of the electrolyte layer away from the positive electrode to obtain an n-type conductive polymer-based water-based supercapacitor.
[0022] Further, in step S1, the concentration of the poly(benzodifuran-dione) solution is 8-12 mg / ml.
[0023] Further, in step S2, the concentration of the neutral salt in the electrolyte solution is 1-5 mol / L.
[0024] The concentration of the hydroquinone and its derivatives is 10-50 mmol / L.
[0025] The application has the following beneficial effects:
[0026] The application applies the n-type conductive polymer PBFDO to the construction of the electrode material of the supercapacitor, and the prepared electrode exhibits excellent electrochemical performance in a three-electrode system.
[0027] In addition, by using the electrolyte solution containing hydroquinone (HQ) and its derivatives and a neutral salt, the pseudo-capacitance capacity of the capacitor can be significantly improved.
[0028] In addition, the HQ and its derivatives can further enhance the stability and improve the cycle life. Experimental results show that by adjusting the addition concentration of HQ, the specific capacitance of the PBFDO water-based symmetric supercapacitor device is increased by more than 50%, reaching about 60 F g -1 Meanwhile, the capacity is maintained at more than 92% after 50,000 cycles. This strategy breaks the traditional bottleneck of n-type conjugated polymers in energy density and electrochemical stability, and demonstrates the broad prospects of high-performance organic energy storage devices through the synergistic design of materials and electrolytes. BRIEF DESCRIPTION OF DRAWINGS
[0029] Figure 1A partial structure schematic diagram of the n-type conductive polymer electrode-based aqueous supercapacitor of the present application.
[0030] Figure 2 A three-electrode cyclic voltammetry curve (CV) of the n-type conductive polymer PBFDO electrode prepared in Preparation Example 1 of the present application.
[0031] Figure 3 A three-electrode galvanostatic charge-discharge curve (GCD) of the n-type conductive polymer PBFDO electrode prepared in Preparation Example 1 of the present application.
[0032] Figure 4 A three-electrode galvanostatic charge-discharge cycle stability test of the n-type conductive polymer PBFDO electrode prepared in Preparation Example 1 of the present application.
[0033] Figure 5 A CV curve comparison of the n-type conductive polymer-based aqueous supercapacitors of Example 2 and Comparative Example 1.
[0034] Figure 6 A GCD curve comparison of the n-type conductive polymer-based aqueous supercapacitors prepared in Example 1, Example 2 and Comparative Example 1.
[0035] Figure 7 A GCD cycle stability comparison of the n-type conductive polymer-based aqueous supercapacitors prepared in Example 2 and Comparative Example 1.
[0036] Figure 8 A GCD cycle stability test of the n-type conductive polymer-based supercapacitor of Example 3 of the present application.
[0037] Figure 9 A device assembly structure schematic diagram of the n-type conductive polymer electrode-based aqueous supercapacitor of the present application. DETAILED DESCRIPTION
[0038] In order to more clearly illustrate the technical solutions of the present application, the following examples are listed. The raw materials, reactions and post-treatment means appearing in the examples are all common raw materials on the market and technical means well known to those skilled in the art, unless otherwise stated.
[0039] The words "preferred", "preferably", "more preferred", etc. in the present application refer to the embodiments of the present application that can provide certain beneficial effects in certain cases. However, other embodiments can also be preferred in the same or other cases. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not usable, nor is it intended to exclude other embodiments from the scope of the present application.
[0040] It should be understood, that all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as approximations based on the desired properties sought to be obtained by the inventors. Therefore, unless otherwise indicated, the numerical parameters set forth in the following specification and attached claims are approximations that can vary. It is intended that the application can be practiced otherwise than the examples that are given.
[0041] Water-based separator, hydrophilic separator series Celgard 3501 NKK cellulose separator.
[0042] Positive shell, negative shell, Colud stainless steel button cell shell CR2032.
[0043] Preparation Example 1
[0044] A method for preparing an n-type conductive polymer electrode comprises the following steps:
[0045] S1-1, Preparation of poly(benzodifuran diketone) solution:
[0046] The oxidant 2,3,5,6-tetramethyl 1,4-benzoquinone (2.7g) and 3,7-dihydrobenzo[1,2-b:4,5-b]difuran-2,6-dione (1.9g) were dissolved in 127ml of ultra-dry dimethyl sulfoxide. The reaction solution was reacted at 90℃ under nitrogen atmosphere for 3h, and 40ml of ultra-dry dimethyl sulfoxide was continuously added under nitrogen protection, and the reaction was continuously stirred for about 3h. After the reaction was completed, the product was transferred to a 10kDa dialysis bag, and dialysis was performed using dimethyl sulfoxide to remove small molecular weight impurities in the reaction solution. After dialysis, an n-type conductive polymer solution was obtained, and the solution concentration was set to 10mg / ml, and the solvent was dimethyl sulfoxide solution;
[0047] S1-2, Treatment of current collector:
[0048] The carbon paper with a size of 10mm*10mm was sequentially treated with acetone, anhydrous ethanol, and deionized water under ultrasonic treatment to ensure that the surface of the carbon paper was clean and impurities and grease were removed. The treated current collector was dried at room temperature for standby use;
[0049] S1-3, 10mg / ml of poly(benzodifuran diketone) solution was drop-coated on the current collector, and dried at 60℃ under vacuum environment for 6h to obtain positive electrode and negative electrode, respectively.
[0050] Example 1
[0051] A partial structure diagram of an n-type conductive polymer-based supercapacitor is shown in Figure 1 The structure comprises the following structures in sequence: positive electrode (153μm), electrolyte layer (200μm), negative electrode (153μm), gasket (300μm).
[0052] wherein the structure of the positive electrode and the negative electrode is poly(benzodifuran-dione) layer (3 μm), current collector layer (150 μm);
[0053] the electrolyte layer comprises a water-based separator and an electrolyte infiltrating the water-based separator;
[0054] The preparation method of the n-type conductive polymer-based supercapacitor, the device assembly structure is as shown in Figure 9 The preparation method of the n-type conductive polymer-based supercapacitor, the device assembly structure is as shown in
[0055] S2, the positive and negative electrodes are pre-placed in the electrolyte solution and soaked for more than 6h for standby;
[0056] S3, the positive electrode is placed in the positive electrode shell of the button cell, then the water-based separator is placed on the poly(benzodifuran-dione) layer of the positive electrode, and 200 μl of electrolyte solution is coated, so that the electrolyte completely infiltrates the water-based separator to form an electrolyte layer;
[0057] wherein the electrolyte solution is a 2M sodium chloride aqueous solution containing 10mM hydroquinone (HQ);
[0058] S4, the negative electrode is placed on the side of the electrolyte layer away from the positive electrode, so that the poly(benzodifuran-dione) layer of the negative electrode is in contact with the electrolyte layer, then the gasket (300 μm) and the spring are sequentially placed, and the negative electrode shell is covered, and the n-type conductive polymer-based water-based supercapacitor is obtained after compression.
[0059] Example 2
[0060] An n-type conductive polymer-based supercapacitor, the partial structure of which is as shown in Figure 1 The structure sequentially comprises the following structures: positive electrode (153 μm), electrolyte layer (200 μm), negative electrode (153 μm);
[0061] wherein the structure of the positive electrode and the negative electrode is poly(benzodifuran-dione) layer (3 μm), current collector layer (150 μm);
[0062] the electrolyte layer comprises a water-based separator and an electrolyte infiltrating the water-based separator;
[0063] The preparation method of the n-type conductive polymer-based supercapacitor, the device assembly structure is as shown in Figure 9 The preparation method of the n-type conductive polymer-based supercapacitor, the device assembly structure is as shown in
[0064] S2, the positive and negative electrodes are pre-placed in the electrolyte solution and soaked for more than 6h for standby;
[0065] S3, placing the positive electrode in the positive electrode shell of the button cell, then placing the water-based separator on the poly(benzodifuran-dione) layer of the positive electrode, then coating 200 μl of the electrolyte solution, and waiting for the electrolyte to completely soak the water-based separator to form an electrolyte layer;
[0066] The electrolyte solution is a 2M sodium chloride aqueous solution containing 20 mM hydroquinone (HQ);
[0067] S4, placing the negative electrode on the side of the electrolyte layer away from the positive electrode, so that the poly(benzodifuran-dione) layer of the negative electrode is in contact with the electrolyte layer, then placing a gasket (300 μm) and a spring in sequence, covering the negative electrode shell, and obtaining the n-type conductive polymer-based water-based supercapacitor after compression.
[0068] Example 3
[0069] An n-type conductive polymer-based supercapacitor, a partial structure of which is shown in Figure 1 The structure includes, in sequence, a positive electrode (153 μm), an electrolyte layer (200 μm), and a negative electrode (153 μm);
[0070] The positive electrode and the negative electrode each have a poly(benzodifuran-dione) layer (3 μm) and a current collector layer (150 μm);
[0071] The electrolyte layer includes a water-based separator and an electrolyte soaked in the water-based separator;
[0072] A method for preparing the n-type conductive polymer-based supercapacitor, a device assembly structure of which is shown in Figure 9 The method includes the following steps:
[0073] S2, pre-soaking the positive and negative electrodes in the electrolyte solution for more than 6 hours for standby;
[0074] S3, placing the positive electrode in the positive electrode shell of the button cell, then placing the water-based separator on the poly(benzodifuran-dione) layer of the positive electrode, then coating 200 μl of the electrolyte solution, and waiting for the electrolyte to completely soak the water-based separator to form an electrolyte layer;
[0075] The electrolyte solution is a 2M sodium chloride aqueous solution containing 20 mM 2,5-dihydroxybenzenesulfonic acid potassium (SHQ);
[0076] S4, placing the negative electrode on the side of the electrolyte layer away from the positive electrode, so that the poly(benzodifuran-dione) layer of the negative electrode is in contact with the electrolyte layer, then placing a gasket (300 μm) and a spring in sequence, covering the negative electrode shell, and obtaining the n-type conductive polymer-based water-based supercapacitor after compression.
[0077] Comparative Example 1
[0078] A capacitor, the difference between the present comparative example and Example 1 is that in step S2, only 2M sodium chloride aqueous solution is used as electrolyte solution, and other components and preparation methods are the same.
[0079] Test Example 1
[0080] The n-type conductive polymer electrode prepared in Preparation Example 1 was subjected to cyclic voltammetry (CV) electrochemical analysis using a CHI660E electrochemical analyzer in a three-electrode system. The three-electrode cell measurement included a working electrode to which the n-type conductive polymer was attached, a platinum wire counter electrode, and a saturated calomel reference electrode. The test was performed in a 2M NaCl aqueous electrolyte (10 mL).
[0081] Figure 2 The CV test curve of the n-type conductive polymer electrode material of Preparation Example 1 in a three-electrode system is shown in the figure. As can be seen from the figure, the material stably works in a voltage window of -0.8V to 0V, the CV curve is close to a rectangle, showing good capacitive behavior, and is suitable for stable charge and discharge operation.
[0082] Test Example 2
[0083] The n-type conductive polymer electrode of Preparation Example 1 was subjected to galvanostatic charge and discharge (GCD) analysis using a CHI660E electrochemical analyzer in a three-electrode system. The three-electrode cell measurement included a working electrode to which the n-type conductive polymer was attached, a platinum wire counter electrode, and a saturated calomel (SCE) reference electrode. The test was performed in a 2M NaCl aqueous electrolyte (10 mL), and cyclic voltammetry (CV) was used for testing. A constant charge / discharge current density of 1Ag -1 to 10Ag -1 was applied, and the potential window was set to 0V to -0.8V vs SCE. The specific capacitance (Cs) can be calculated from the GCD curve according to the following equation:
[0084] C s = IΔt / mΔV.
[0085] I is the constant discharge current; Δt is the discharge time; m is the mass of the active material; and ΔV is the discharge voltage drop.
[0086] Figure 3 The galvanostatic charge and discharge curves of the n-type conductive polymer electrode material prepared under the conditions of Preparation Example 1 at different current densities in a three-electrode system are shown in the figure, which shows the charge and discharge process of the electrode material at different current densities, and reflects its good charge and discharge stability and high specific capacity; it can be seen that at a current density of 1Ag -1 , the electrode material exhibits a mass specific capacity of 198.75F·g -1 , and at a current density of 2Ag -1 , it still maintains a mass specific capacity of 198.75F·g-1 The specific capacity is maintained at 197.125 F g -1 at a current density of 10 Ag -1 , showing that the electrode material has excellent specific capacity retention at different current densities.
[0087] Figure 4 The stability test results of the n-type conductive polymer electrode material prepared under the conditions of Preparation Example 1 in a three-electrode system, the figure shows the capacity retention rate of the electrode material under long-time high-current charge-discharge cycling, proving the high stability and long cycle life of the electrode material. It can be seen that at a current density of 10 Ag -1 , after 5000 charge-discharge cycles, the capacity retention rate of the material is 90%, indicating that the n-type conductive polymer PBFDO has excellent long-term cycle stability.
[0088] Test Example 3
[0089] The n-type conductive polymer-based aqueous supercapacitors prepared in Comparative Example 1 and Example 2 were subjected to cyclic voltammetry (CV) electrochemical analysis using a CHI660E electrochemical analyzer.
[0090] Figure 5 The CV curves of the n-type conductive polymer-based aqueous supercapacitors of Comparative Example 1 and Example 2 are compared. The figure shows that the CV curve of the aqueous supercapacitor prepared in Example 2 using the HQ modified electrolyte system has a significantly larger enclosed area than the control group of Comparative Example 1 without adding HQ, indicating that HQ provides significant pseudocapacitance contribution, thereby improving the overall specific capacitance of the device.
[0091] Test Example 4
[0092] The n-type conductive polymer-based aqueous supercapacitors prepared in Comparative Example 1, Example 1 and Example 2 were subjected to galvanostatic charge-discharge (GCD) analysis using a CHI660E electrochemical analyzer.
[0093] Figure 6 The GCD curves of the n-type conductive polymer-based aqueous supercapacitors prepared in Comparative Example 1, Example 1 and Example 2 are compared. The figure shows that under the condition of HQ concentration of 20 mM and current density of 1 Ag -1 , the specific capacitance of the device can reach nearly 60 F g -1 , which is more than 50% higher than that without adding HQ.
[0094] Figure 7 The GCD cycle stability of the n-type conductive polymer-based aqueous supercapacitors prepared in Comparative Example 1 and Example 2 is compared.
[0095] The image shows 30Ag -1 After 50,000 charge-discharge cycles under the conditions, the HQ-modified device still retains more than 93% of its initial capacitance, while the undoped device retains only about 74%, demonstrating the positive effect of the HQ additive proposed in this patent in extending cycle life.
[0096] Test Example 5
[0097] The aqueous supercapacitor based on n-type conductive polymer prepared in Example 3 was analyzed by constant current charge-discharge (GCD) using a CHI660E electrochemical analyzer.
[0098] Figure 8 The figure shows the GCD cycle stability test of the n-type conductive polymer-based supercapacitor in Example 3 of this invention, at 30 Ag. -1 After 50,000 charge-discharge cycles under the specified conditions, the SHQ-modified device exhibits a capacitance retention rate of over 90%, demonstrating the versatility of the proposed method of using hydroquinone and its derivatives as electrolytes in extending the cycle life of n-type conductive polymer-based supercapacitors.
[0099] Figure 9 This is a schematic diagram of the device assembly structure of an aqueous supercapacitor with an n-type conductive polymer electrode used in the testing of a dual-electrode device in Comparative Examples 1, Examples 1, 2, and 3 of the present invention.
[0100] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.
[0101] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. An n-type conductive polymer-based supercapacitor, characterized in that, The n-type conductive polymer-based supercapacitor comprises the following structure in sequence: a positive electrode, an electrolyte layer, and a negative electrode; The positive and negative electrodes are composed of a poly(benzodifuran dione) (PBFDO) layer and a current collector layer. The electrolyte layer comprises an aqueous membrane and an electrolyte that wets the aqueous membrane, wherein the electrolyte material is selected from one or more of neutral salts and hydroquinone and its derivatives.
2. The n-type conductive polymer-based supercapacitor according to claim 1, characterized in that, The neutral salt is selected from one or more of sodium chloride, potassium chloride, and lithium chloride.
3. The n-type conductive polymer-based supercapacitor according to claim 1, characterized in that, The structures of hydroquinone and its derivatives are shown below: Wherein, R is selected from one or more of hydrogen, alkyl, alkyl derivatives, sulfonates, carboxyl, and hydroxyl groups; One or more carbon atoms on the alkyl derivative are substituted by one or more of an oxygen atom, sulfone group, sulfoxide group, carbonyl group, aryl group, olefin group, alkyne group, ester group, cyano group, or nitro group.
4. The n-type conductive polymer-based supercapacitor according to claim 1, characterized in that, The material of the current collector layer is selected from one or more of carbon paper, carbon cloth, graphite, copper foil, or nickel foam.
5. The n-type conductive polymer-based supercapacitor according to claim 1, characterized in that, The material of the water-based diaphragm is one or more of cellulose paper, polypropylene, and PAN / PVDF-HFP.
6. The method for preparing the n-type conductive polymer-based supercapacitor according to any one of claims 1-5, characterized in that, Includes the following steps: S1. The poly(benzodifurandione) solution is drop-coated onto the current collector to obtain the positive and negative electrodes, respectively; S2. Place an aqueous membrane on the positive electrode, then coat it with an electrolyte solution. Wait for the electrolyte to completely wet the aqueous membrane to form an electrolyte layer. S3. Place the negative electrode on the side of the electrolyte layer away from the positive electrode to obtain an n-type conductive polymer-based aqueous supercapacitor.
7. The method for preparing the n-type conductive polymer-based supercapacitor according to claim 6, characterized in that, In step S1, the concentration of the poly(benzodifurandione) solution is 8-12 mg / ml.
8. The method for preparing the n-type conductive polymer-based supercapacitor according to claim 6, characterized in that, In step S2, the concentration of the neutral salt in the electrolyte solution is 1-5 mol / L.
9. The method for preparing the n-type conductive polymer-based supercapacitor according to claim 6, characterized in that, In step S2, the concentration of hydroquinone and its derivatives in the electrolyte solution is 10-50 mmol / L.