A method for preparing a porous heterojunction vanadium-based aqueous zinc battery cathode and its application.

Abstract

This application discloses a method for preparing a porous heterojunction vanadium-based aqueous zinc battery cathode and its application. First, FeCl3·6H2O and fumaric acid are dissolved in deionized water and stirred vigorously. The suspension is then transferred to a round-bottom flask for oil bath treatment. After cooling, the solution is washed and dried to obtain product MIL-88A. Next, NH4VO3 is dissolved in deionized water and stirred in an oil bath until completely dissolved. MIL-88A is dispersed in ethanol and added dropwise to the NH4VO3 solution with stirring. After cooling to room temperature, the solid product is centrifuged with water and ethanol respectively, and finally vacuum dried. The product is then heated using a muffle furnace to obtain a FeVO3 porous heterojunction oxide. This cathode material can reduce the zinc ion diffusion barrier, improve electron transport generated by the built-in electric field at the interface, and significantly improve its rate performance. The porous structure formed by its activation can reduce the diffusion barrier and improve the structural stability of the aqueous zinc battery cathode.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of modification of positive electrodes of aqueous zinc batteries, and particularly relates to a preparation method of a porous heterojunction vanadium-based positive electrode of an aqueous zinc battery and application thereof. BACKGROUND

[0002] In recent years, aqueous zinc batteries (AZIBs) have rapidly developed among all aqueous rechargeable batteries. First, zinc is abundant in the earth's crust, with a content of about 0.013%, and has a relatively low cost. In addition, the metal zinc negative electrode has a low electrode potential (-0.76 V vs. SHE) and a high enough specific capacity (820 mAh·g -1 ) and volume specific capacity (5851 mAh·cm -3 ). Second, AA and AAA alkaline dry batteries widely used in daily life are aqueous batteries based on a metal zinc negative electrode, which indicates the superiority of the metal zinc negative electrode. To date, the development of aqueous zinc secondary batteries has rapidly expanded the research and development of positive electrode materials from manganese-based materials to vanadium-based compounds, Prussian blue and its derivatives, and carbonyl organic compounds.

[0003] However, due to the decomposition voltage of water, there are relatively few positive electrode materials that can achieve efficient reversible intercalation / deintercalation of zinc ions. Therefore, the development of positive electrode materials for aqueous zinc batteries with high specific capacity and high stability is still one of the main directions of research in the field of aqueous zinc batteries. SUMMARY

[0004] Technical problems solved:

[0005] The present application solves the technical problems that, due to the decomposition voltage of water, there are relatively few positive electrode materials that can achieve efficient reversible intercalation / deintercalation of zinc ions, and provides a preparation method of a porous heterojunction vanadium-based positive electrode of an aqueous zinc battery and application thereof. The FeVO porous heterojunction oxide is prepared by using an iron-based MOFs material as a raw material and adopting a template sacrifice method to dope vanadium elements. The positive electrode material has a porous heterojunction structure, can reduce diffusion barriers, improve electron transmission, and make the electrode have excellent rate performance, superior cycle stability, and high capacity.

[0006] Technical scheme:

[0007] To achieve the above-mentioned purpose, the present application is implemented by the following technical scheme:

[0008] A preparation method of a porous heterojunction vanadium-based positive electrode of an aqueous zinc battery, the steps being as follows:

[0009] First step: synthesis of MIL-88A

[0010] S1, under room temperature conditions, FeCl3·6H2O 1.35 g and fumaric acid 0.58 g were weighed according to the mass-volume ratio and dissolved in deionized water 100 mL respectively to obtain a ferric chloride solution and a fumaric acid solution;

[0011] S2, the ferric chloride solution was introduced into the fumaric acid solution, and stirred vigorously for 25-30 min, and then the mixed solution was transferred to a round-bottom flask in an oil bath at 100℃ for 4h;

[0012] S3, when cooled to room temperature, the product was collected with a centrifuge, and deionized water and ethanol were used to wash 3 times respectively; finally, MIL-88A was obtained by drying in a vacuum drying oven at 60℃-80℃ for 12h;

[0013] Second step, synthesis of FeVO oxide:

[0014] Step a, 1.053 g of NH4VO3 was added to 50 mL of deionized water according to the mass-volume ratio, and stirred vigorously in an oil bath at 70℃-80℃ for 1h to obtain a NH4VO3 solution;

[0015] Step b, the previously prepared MIL-88A 0.414 g was uniformly dispersed in 20 mL of ethanol according to the mass-volume ratio, and the NH4VO3 solution was added dropwise, and the stirring was continued for 1.5-2h to obtain a reaction mixture;

[0016] Step c, when the reaction mixture was naturally cooled to room temperature, it was centrifuged 3-5 times with deionized water and ethanol, and the product was dried in a vacuum drying oven at 60℃-80℃ for 12h;

[0017] Step d, the dried product was transferred to a muffle furnace and calcined at 400℃ under air atmosphere at a heating rate of 2℃ / min for 2h to obtain the product, which was denoted as FeVO oxide;

[0018] Third step: active material FeVO oxide 60%-80% by mass percentage; conductive additive 10%-30%; the rest is binder, the total amount is 100%;

[0019] Fourth step: mix FeVO oxide, conductive additive and binder uniformly, add 1-2 mL of isopropanol dropwise to the mixture until the surface of the mixture is smooth, and then roll the mixture into an electrode film, and finally press the electrode film on the mesh current collector to obtain a porous heterojunction vanadium-based aqueous zinc battery positive electrode.

[0020] Further, the conductive additive in the third step is one or more of Ketjen black KB, activated carbon, mesoporous carbon, graphene, carbon nanotube, carbon fiber, acetylene black and carbon black; and the binder is one of polytetrafluoroethylene PTFE, polyvinylidene fluoride, polyolefin, polyvinyl alcohol and styrene rubber.

[0021] Further, the binder is a polytetrafluoroethylene dispersion liquid, and the mass concentration is 40% to 60%.

[0022] Further, the mesh current collector in the fourth step is a titanium mesh, a nickel mesh, or a stainless steel mesh.

[0023] The application also discloses application of the porous heterojunction vanadium-based water-based zinc battery anode prepared by any one of the preparation methods to a fast-charging and fast-discharging water-based zinc battery or a water solution battery.

[0024] Further, the fast-charging and fast-discharging water-based zinc battery uses metal zinc as a negative electrode material, and an electrolyte is a zinc ion electrolyte.

[0025] Further, the negative electrode material is 0.015 mm thin zinc, 0.035 mm medium zinc, or 0.075 mm thick zinc.

[0026] Further, the zinc ion electrolyte is Zn(OTf)2, Zn(ClO) 4、 ZnSO4, or ZnCl2.

[0027] Further, the zinc ion electrolyte contains zinc ions at a concentration of 0.01 mol / L to 10 mol / L.

[0028] Further, the porous heterojunction vanadium-based water-based zinc battery anode, a glass fiber separator, and a zinc foil electrode are stacked together to form a "sandwich" structure, a 3M Zn(OTf)2 aqueous solution is used as an electrolyte, and a vacuum sealing process is used to prepare a strip-shaped Zn / / FeVO oxide water-based battery.

[0029] Original explanation: the reason why the FeVO oxide material has excellent performance lies in its unique structural and component characteristics and good adsorption and diffusion characteristics. From the structure, it has a porous heterostructure, and the built-in electric field is formed due to the difference in work function and band gap, which promotes charge separation and transmission. At the same time, the rich pores bring a high specific surface area of mesoporous structure, which is beneficial to electrolyte penetration and ion diffusion. From the composition, the multi-valence of iron and vanadium produces multiple redox reactions during charging and discharging, increases the charge storage and improves the capacity, and the interaction between elements stabilizes the structure and improves the cycle stability. In terms of adsorption and diffusion, Fe2V4O 13 adsorbs Zn 2+ has strong capacity, low adsorption energy, and many sites, enhances adsorption kinetics, and Zn 2+ diffusion coefficient is high, ion migration is fast, thereby improving the rate performance and charging and discharging efficiency.

[0030] Beneficial effects:

[0031] The application provides a preparation method of a porous heterojunction vanadium-based aqueous zinc battery positive electrode and application thereof, and has the following beneficial effects compared with the prior art:

[0032] 1. The application solves a series of problems of zinc battery positive electrodes, has low preparation cost, can be mass-produced, and thus realizes marketization;

[0033] 2. The preparation method of the porous heterojunction vanadium-based aqueous zinc battery positive electrode has a porous heterojunction structure, a built-in electric field formed in the process of optimizing the electronic structure responds quickly, and can quickly promote charge transport;

[0034] 3. The zinc battery FeVO oxide positive electrode prepared in the application has a discharge capacity of 431 mAh·g -1 and a cycle of 100 times at a current density of 0.6 A·g -1 , and exhibits high capacity characteristics;

[0035] 4. The zinc battery FeVO oxide positive electrode prepared in the application can still maintain good capacity and cycle stability at a high current density at a current density of 40 A·g -1 , has a cycle of 12000 times, and has a capacity retention rate of 95%;

[0036] 5. The zinc battery FeVO oxide positive electrode prepared in the application has similar charge-discharge curves when the current density gradually increases from 0.6 A·g -1 to 80 A·g -1 , and still has a high capacity of 250 mAh·g -1 at 80 A·g -1 (11s charging time), which indicates excellent rate performance. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a micro-morphology diagram of the porous heterojunction vanadium-based aqueous zinc battery positive electrode of the application;

[0038] Figure 2 is an XRD powder diffraction diagram of the vanadium-based material of the application;

[0039] Figure 3 is a cycle performance diagram of the application at a current density of 0.6 A·g -1 ;

[0040] Figure 4 is a cycle performance diagram of the application at a current density of 40 A·g -1 ;

[0041] Figure 5 is a current density from 0.6 A·g -1Gradually increased to 80 A·g -1 The rate constant current charge-discharge curve under the following. DETAILED DESCRIPTION

[0042] The application will be described in detail below with specific examples. The following examples will help those skilled in the art to further understand the application, but in no way limit the application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made. These are within the scope of the present application.

[0043] Example 1

[0044] A method for preparing a porous heterojunction vanadium-based aqueous zinc battery anode, the steps are as follows:

[0045] First, the synthesis of MIL-88A:

[0046] S1, under room temperature conditions, according to the mass volume ratio, FeCl3·6H2O 1.35g and fumaric acid 0.58g were weighed into deionized water 100mL respectively, mixed uniformly to obtain iron chloride solution and fumaric acid solution;

[0047] S2, the iron chloride solution was introduced into the fumaric acid solution, and stirred vigorously for 30 min, then the mixed solution was transferred to a round mouth flask, and the oil bath was 100℃ for 4h;

[0048] S3, when cooled to room temperature, the product was collected with a centrifuge, and deionized water and ethanol were used to wash 3 times respectively; Finally, in a vacuum drying oven at 80℃, vacuum drying oven was dried for 12h to obtain MIL-88A;

[0049] Second, the synthesis of FeVO oxide:

[0050] Step a, according to the mass volume ratio, 1.053g NH4VO3 was added into 50mL deionized water, and stirred vigorously in oil bath at 70℃-80℃ for 1h to obtain NH4VO3 solution;

[0051] Step b, according to the mass volume ratio, the previously prepared MIL-88A 0.414 g was uniformly dispersed in 20mL ethanol, and NH4VO3 solution was added dropwise, and stirring was continued for 2h;

[0052] Step c, when the reaction mixture was naturally cooled to room temperature, it was centrifuged with deionized water and ethanol for 3-5 times, and the product was vacuum dried at 60℃ for 12h;

[0053] Step d, the dried product was transferred to a muffle furnace, calcined at 400℃ under air atmosphere at a heating rate of 2℃ / min for 2h to obtain the product, which was denoted as FeVO oxide;

[0054] Third step: 60% active material FeVO oxide; 30% conductive additive KB; 10% PTFE by mass percentage;

[0055] Fourth step: FeVO oxide is mixed with conductive additive and binder, 1-2 mL of isopropyl alcohol is added dropwise to the mixture until the surface of the mixture is smooth, an electrode film is made by rolling, and finally the electrode film is pressed on the mesh current collector titanium mesh to obtain a positive electrode.

[0056] Application of porous heterojunction vanadium-based aqueous zinc battery positive electrode in fast charging and discharging aqueous zinc battery, with metal zinc as negative electrode material and zinc ion electrolyte as electrolyte. According to the sequence of negative electrode shell, two titanium meshes, 0.015 mm thin Zn, glass fiber diaphragm, porous heterojunction vanadium-based aqueous zinc battery positive electrode, and positive electrode shell, a CR2016 button cell is assembled by using 3 mol·L -1 Zn(OTf)2 aqueous solution as electrolyte through battery packaging machine packaging operation.

[0057] Example 2

[0058] A method for preparing a porous heterojunction vanadium-based aqueous zinc battery positive electrode, comprising the following steps:

[0059] First step, synthesis of MIL-88A:

[0060] S1, under room temperature conditions, weigh FeCl3·6H2O 1.35g and fumaric acid 0.58g in a mass-volume ratio and dissolve in deionized water 100mL respectively, mix uniformly to obtain iron chloride solution and fumaric acid solution;

[0061] S2, introduce the iron chloride solution into the fumaric acid solution, stir vigorously for 30 min, then transfer the mixed solution to a round-mouth flask, and heat in an oil bath at 100℃ for 4h;

[0062] S3, when cooled to room temperature, collect the product with a centrifuge, and wash with deionized water and ethanol for 3 times respectively; finally dry in a vacuum drying oven at 80℃ for 12h to obtain MIL-88A;

[0063] Second step, synthesis of FeVO oxide:

[0064] Step a, add 1.053g NH4VO3 to 50mL deionized water in a mass-volume ratio, and stir vigorously in an oil bath at 70-80℃ for 1h to obtain NH4VO3 solution;

[0065] Step b, the pre-prepared MIL-88A 0.414 g was uniformly dispersed in 20 mL of ethanol by mass volume ratio, and NH4VO3 solution was added dropwise, and stirring was continued for 2 h;

[0066] Step c, when the reaction mixture was naturally cooled to room temperature, it was centrifuged 3-5 times with deionized water and ethanol, and the product was vacuum dried at 60℃ for 12 h;

[0067] Step d, the dried product was transferred to a muffle furnace and calcined at 400℃ under air atmosphere at a heating rate of 2℃ / min for 2 h to obtain the product, denoted as FeVO oxide;

[0068] Third step: by mass percentage: active material FeVO oxide: 60%; conductive additive KB 30%; PTFE 10%;

[0069] Fourth step: the FeVO oxide was uniformly mixed with the conductive additive and the binder, 1-2 mL of isopropanol was added dropwise to the mixture until the surface of the mixture was smooth, and the electrode film was made by rolling, and finally the electrode film was pressed on the mesh current collector zinc foil to obtain the positive electrode.

[0070] Application of porous heterojunction vanadium-based aqueous zinc battery positive electrode in fast charging and discharging aqueous solution battery, the porous heterojunction vanadium-based aqueous zinc battery positive electrode, glass fiber separator and zinc foil electrode were stacked together to form

[0071] Sandwich structure, 3M Zn(OTf)2 aqueous solution as electrolyte, vacuum sealing process to prepare ribbon Zn / / FeVO oxide aqueous solution battery.

[0072] Example 3

[0073] A method for preparing a porous heterojunction vanadium-based aqueous zinc battery positive electrode, the steps are as follows:

[0074] First step, synthesis of MIL-88A:

[0075] S1, under room temperature conditions, FeCl3·6H2O 1.35 g and fumaric acid 0.58 g were weighed and dissolved in deionized water 100 mL respectively according to the mass volume ratio, and mixed uniformly to obtain the iron chloride solution and fumaric acid solution;

[0076] S2, the iron chloride solution was introduced into the fumaric acid solution, and stirred vigorously for 30 min, and then the mixed solution was transferred to a round-mouth flask and heated in an oil bath at 100℃ for 4 h;

[0077] S3, when cooled to room temperature, the product was collected with a centrifuge, and washed with deionized water and ethanol for 3 times respectively; finally dried in a vacuum drying oven at 80℃ for 12 h to obtain MIL-88A;

[0078] Second step, synthesis of FeVO oxide:

[0079] Step a, 1.053 g of NH4VO3 was added to 50 mL of deionized water according to the mass volume ratio, and 1 h of vigorous stirring was carried out in an oil bath at 70-80°C to obtain an NH4VO3 solution;

[0080] Step b, the pre-prepared MIL-88A 0.414 g was uniformly dispersed in 20 mL of ethanol according to the mass volume ratio, and the NH4VO3 solution was added dropwise, and stirring was continued for 2 h;

[0081] Step c, when the reaction mixture is naturally cooled to room temperature, centrifuge with deionized water and ethanol 3-5 times, and vacuum dry the product at 60°C for 12 h;

[0082] Step d, the dried product was transferred to a muffle furnace and calcined at 400°C under air atmosphere at a heating rate of 2°C / min for 2 h to obtain the product, which is denoted as FeVO oxide;

[0083] Third step: according to the mass percentage: active material FeVO oxide: 70%; conductive additive acetylene black 20%; PTFE 10%;

[0084] Fourth step: mix the FeVO oxide with the conductive additive and the binder uniformly, add 1-2 mL of isopropanol dropwise to the mixture until the surface of the mixture is smooth, and then roll the mixture into an electrode film, and finally press the electrode film onto the mesh current collector titanium mesh to obtain the positive electrode.

[0085] Application of porous heterojunction vanadium-based aqueous zinc battery positive electrode in fast charging and discharging aqueous zinc battery, with metal zinc as negative electrode material and zinc ion electrolyte as electrolyte. According to the sequence of negative electrode shell, two pieces of titanium mesh, 0.075 mm thick Zn, glass fiber separator, porous heterojunction vanadium-based aqueous zinc battery positive electrode, and positive electrode shell, a CR2016 button cell is assembled by using 3 mol·L -1 Zn(OTf)2 aqueous solution as electrolyte through battery packaging machine packaging operation. Denoted as Zn / / FeVO oxide button cell.

[0086] Example 4

[0087] A method for preparing a porous heterojunction vanadium-based aqueous zinc battery positive electrode, the steps are as follows:

[0088] First step, synthesis of MIL-88A:

[0089] S1, under room temperature conditions, weigh FeCl3·6H2O 1.35 g and fumaric acid 0.58 g according to the mass volume ratio, and dissolve them in 100 mL of deionized water respectively, and mix uniformly to obtain a ferric chloride solution and a fumaric acid solution;

[0090] S2, the ferric chloride solution was introduced into the fumaric acid solution, and stirred vigorously for 30 min, and then the mixed solution was transferred to a round-bottom flask and heated in an oil bath at 100℃ for 4h;

[0091] S3, when cooled to room temperature, the product was collected with a centrifuge, and washed with deionized water and ethanol for 3 times respectively; finally dried in a vacuum drying oven at 80℃ for 12h to obtain MIL-88A;

[0092] Second step, synthesis of FeVO oxide:

[0093] Step a, 1.053g NH4VO3 was added to 50mL deionized water according to the mass volume ratio, and stirred vigorously in an oil bath at 70-80℃ for 1h to obtain a NH4VO3 solution;

[0094] Step b, the previously prepared MIL-88A 0.414 g was uniformly dispersed in 20mL ethanol according to the mass volume ratio, and the NH4VO3 solution was added dropwise, and the stirring was continued for 2h;

[0095] Step c, when the reaction mixture was naturally cooled to room temperature, the product was centrifuged 3-5 times with deionized water and ethanol, and dried in a vacuum drying oven at 60℃ for 12h;

[0096] Step d, the dried product was transferred to a muffle furnace and calcined at 400℃ under air atmosphere at a heating rate of 2℃ / min for 2h to obtain the product, which was denoted as FeVO oxide;

[0097] Third step: active material FeVO oxide: 70%; conductive additive KB 20%; PTFE 10% by mass percentage;

[0098] Fourth step: the FeVO oxide was mixed with the conductive additive and the binder, 1-2mL of isopropanol was added dropwise to the mixture until the surface of the mixture was smooth, and the electrode film was made by rolling, and finally the electrode film was pressed on the mesh current collector titanium mesh to obtain the positive electrode.

[0099] Application of porous heterojunction vanadium-based positive electrode of aqueous zinc battery in fast charging and discharging aqueous zinc battery, with metal zinc as negative electrode material and zinc ion electrolyte as electrolyte. According to the sequence of negative electrode shell, two pieces of titanium mesh, 0.075mm thick Zn, glass fiber separator, porous heterojunction vanadium-based positive electrode of aqueous zinc battery, and positive electrode shell, 2mol·L -1 ZnSO4 aqueous solution as electrolyte, packaged by battery packaging machine to assemble CR2016 button cell. Denoted as Zn / / FeVO oxide button cell.

[0100] Scanning electron microscopy (SEM) test:

[0101] The prepared FeVO₃ was subjected to SEM testing to examine its morphology, such as... Figure 1 As shown, the prepared iron-vanadium oxide was found to have a square pyramidal porous structure.

[0102] XRD test:

[0103] The prepared FeVO was subjected to XRD testing and compared with Fe2V4O 13 and Fe 0.12 Standard card comparison of V2O5, such as Figure 2 It shows more peaks, indicating the presence of a mixed-phase heterostructure in the FeVO oxide sample.

[0104] Cyclic performance test:

[0105] like Figure 3 The figure shows the current density at 0.6 A·g -1 The following is a cycle performance graph showing that this electrode battery has a high 431 mAh·g. -1 The specific capacity remains at 428 mAh·g after 100 cycles. -1 The capacity retention rate is as high as 95%.

[0106] Long-cycle performance testing:

[0107] Figure 4 The figure shows the current density at 40 A·g -1 The cycle performance diagram below shows a cycle life of 12,000 cycles, a coulombic efficiency of almost 100%, and a capacity retention rate of up to 95%.

[0108] GCD multiplier test:

[0109] Figure 5 This is at a current density of 0.6 A·g -1 Gradually increase to 80 A·g -1 The constant current charge-discharge curves at a certain rate show that the FeVO oxide cathode exhibits excellent rate capacity at 80 A·g⁻¹. -1 At ultra-high current density, the battery's charging capacity reaches 252.3 mAh·g. -1 Meanwhile, the current density was gradually adjusted to 0.6 A·g -1 The battery's reversible capacity is fully restored.

[0110] The embodiments selected in the above materials are for ease of understanding and not for limiting the process method. Those skilled in the art can easily modify the process flow or transfer it to other cases without inventive change. If these modifications also fall under the category of similar claims or similar technology of this invention, then the intent of this invention also includes these modifications.

Claims

1. A method for preparing a porous heterojunction vanadium-based aqueous zinc battery cathode, characterized in that, The steps are as follows: Step 1: synthesis of MIL-88A: S1: Under room temperature, FeCl3·6H2O 1.35g and fumaric acid 0.58g were weighed according to the mass-volume ratio and dissolved in deionized water 100mL respectively, and mixed uniformly to obtain the iron chloride solution and fumaric acid solution; S2: The iron chloride solution was introduced into the fumaric acid solution, and stirred vigorously for 25-30min, and then the mixed solution was transferred to a round-bottom flask in an oil bath at 100℃ for 4h; S3: When cooled to room temperature, the product was collected by centrifuge, and washed with deionized water and ethanol for 3 times respectively; finally dried in a vacuum drying oven at 60℃-80℃ for 12h to obtain MIL-88A; Step 2: synthesis of FeVO oxide: Step a: 1.053g NH4VO3 was added to 50mL deionized water according to the mass-volume ratio, and stirred vigorously in an oil bath at 70℃-80℃ for 1h to obtain NH4VO3 solution; Step b: The previously prepared MIL-88A 0.414g was uniformly dispersed in 20mL ethanol according to the mass-volume ratio, and the NH4VO3 solution was added dropwise, and the stirring was continued for 1.5-2h to obtain the reaction mixture; Step c: When the reaction mixture was naturally cooled to room temperature, it was centrifuged with deionized water and ethanol for 3-5 times, and the product was dried in a vacuum drying oven at 60℃-80℃ for 12h; Step d: The dried product was transferred to a muffle furnace and calcined at 400℃ under air atmosphere at a heating rate of 2℃ / min for 2h to obtain the product, which was denoted as FeVO oxide; Step 3: The active material FeVO oxide was 60%-80% by mass percentage; the conductive additive was 10%-30% by mass percentage; the rest was the binder, and the total amount was 100%; Step 4: The FeVO oxide, conductive additive and binder were mixed uniformly, 1-2mL of isopropyl alcohol was added dropwise to the mixture until the surface of the mixture was smooth, and the electrode film was prepared by rolling, and finally the electrode film was pressed on the mesh current collector to obtain the porous heterojunction vanadium-based aqueous zinc battery anode.

2. The method for preparing the porous heterojunction vanadium-based aqueous zinc battery cathode according to claim 1, characterized in that: The conductive additive in the third step is one or more of Ketjen black KB, activated carbon, mesoporous carbon, graphene, carbon nanotube, carbon fiber, acetylene black and carbon black; the binder is one of polytetrafluoroethylene PTFE, polyvinylidene fluoride, polyolefin, polyvinyl alcohol and styrene rubber.

3. The method for preparing the porous heterojunction vanadium-based aqueous zinc battery cathode according to claim 2, characterized in that: The binder is polytetrafluoroethylene dispersion liquid, and the mass concentration is 40%-60%.

4. The method for preparing the porous heterojunction vanadium-based aqueous zinc battery cathode according to claim 1, characterized in that: The mesh current collector in the fourth step is titanium mesh, nickel mesh or stainless steel mesh.

5. The porous heterojunction vanadium-based aqueous zinc battery anode prepared by the preparation method of any one of claims 1-4 is applied in a fast charge-discharge aqueous zinc battery or aqueous solution battery.

6. Use according to claim 5, characterized in that: The fast charge-discharge aqueous zinc battery uses metal zinc as the negative electrode material, and the electrolyte is zinc ion electrolyte.

7. Use according to claim 6, characterized in that: The negative electrode material is 0.015mm thin zinc, 0.035mm medium zinc or 0.075mm thick zinc.

8. Use according to claim 6, characterized in that: The zinc ion electrolyte is Zn(OTf)2, Zn(ClO) 4、 ZnSO4or ZnCl2.

9. Use according to claim 8, characterized in that: In the zinc ion electrolyte, the concentration of zinc ions contained is 0.01mol / L-10mol / L.

10. Use according to claim 5, characterized in that: The porous heterojunction vanadium-based aqueous zinc battery positive electrode, glass fiber separator and zinc foil electrode are stacked together to form a "sandwich" structure, 3MZn(OTf)2 aqueous solution is used as electrolyte, and a strip-shaped Zn / / FeVO oxide aqueous battery is prepared by using a vacuum sealing process.

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