Zinc metal materials modified with aramid nanofiber interface layers and their applications as negative electrode materials for aqueous zinc ion batteries

Abstract

The present invention discloses a zinc metal material modified with an aramid nanofiber interface layer and its application as a negative electrode material for aqueous zinc ion batteries, belonging to the technical field of new materials and zinc ion batteries. The preparation method comprises the following steps: (1) using anhydrous ethanol to ultrasonically clean the surface of a zinc foil, drying it, and obtaining a pretreated zinc foil; (2) uniformly scraping an aramid nanofiber solution onto the pretreated zinc foil, drying it through ventilation, and obtaining a zinc metal material with an aramid nanofiber interface layer modified on the surface. The present invention isolates water molecules from direct contact with zinc metal by constructing a hydrophobic, zinc-philic, three-dimensional porous interface layer, thereby enhancing the Zn 2+ The transport kinetics and uniform zinc ion flux can reduce the occurrence of water-induced side reactions, inhibit the formation and growth of zinc dendrites, and make zinc metal materials show excellent stability, which has great development potential and application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of new materials and zinc ion batteries, specifically relates to the technical field of aramid fiber materials and aqueous zinc ion batteries, and in particular relates to a zinc metal material modified with an aramid nanofiber interface layer and its application as a negative electrode material for aqueous zinc ion batteries. Background Art

[0002] Lithium-ion batteries, among electrochemical energy storage devices, are widely used in new energy vehicles, digital products and other equipment due to their advantages such as high energy density and environmental friendliness. However, the large-scale development of lithium-ion batteries is constrained by the bottlenecks of high lithium prices, high risk, and harsh battery production conditions. For example, most lithium-ion batteries use organic solutions as electrolytes, which can easily cause batteries to catch fire and explode. In view of the above-mentioned problems in the production and use of lithium-ion batteries, researchers have focused their attention on aqueous batteries. Aqueous batteries use aqueous solutions as electrolytes, which are flame retardant, can effectively prevent battery spontaneous combustion and explosion, and have strong safety. At the same time, the price of aqueous solution electrolytes is lower than that of organic solution electrolytes for lithium-ion batteries, and the ionic conductivity of aqueous solution electrolytes is much higher than that of organic solution electrolytes.

[0003] Zinc metal as the negative electrode of the battery has the advantages of low cost, high safety, high theoretical specific capacity (820 mAh g) compared with other metals. −1 ) and low redox potential (-0.76 V vs. standard hydrogen electrode). However, the inherent problems of zinc metal itself limit the practical application of aqueous zinc-ion batteries. When it is used in the negative electrode of aqueous zinc-ion batteries, uneven zinc deposition will lead to the formation and growth of zinc dendrites, which will pierce the diaphragm and eventually cause the battery to short-circuit. Zinc dendrites have mechanical rigidity and structural heterogeneity, and they are easy to fall off from the zinc negative electrode to form "dead zinc", resulting in a reduction in active materials and battery capacity degradation. In addition, the occurrence of water-induced side reactions such as hydrogen evolution, corrosion, and passivation leads to reduced battery stability. The above adverse electrochemical reactions limit the development and application of aqueous zinc-ion batteries. Summary of the Invention

[0004] Aiming at the problem of poor stability of zinc metal negative electrode in aqueous zinc ion battery, the present invention provides a zinc metal material modified with aramid nanofiber interface layer and its application as negative electrode material of aqueous zinc ion battery, which isolates water molecules from direct contact with zinc metal by constructing hydrophobic, zinc-philic and three-dimensional porous interface layer, thereby enhancing the stability of Zn 2+ The transport kinetics and uniform zinc ion flux can reduce the occurrence of water-induced side reactions, inhibit the formation and growth of zinc dendrites, and make zinc metal materials show excellent stability, which has great development potential and application prospects.

[0005] In order to achieve the above object, the present invention adopts a method for preparing a zinc metal material modified with an aramid nanofiber interface layer, comprising the following steps:

[0006] (1) Using anhydrous ethanol to clean the surface of the zinc foil by ultrasonic cleaning and drying to obtain a pretreated zinc foil;

[0007] (2) evenly coating the aramid nanofiber solution on the pretreated zinc foil and drying it under ventilation to obtain a zinc metal material with an aramid nanofiber interface layer modified on the surface;

[0008] The aramid nanofiber solution is prepared by the following steps:

[0009] (a) Place PPTA and KOH in a beaker, add DMSO solution and deionized water, and stir.

[0010] (b) Deionized water is added continuously with stirring, and the stirred solution is filtered to collect the aramid nanofibers;

[0011] (c) dispersing the aramid nanofibers in deionized water, vacuum filtering, collecting the aramid nanofibers, and redispersing them in anhydrous ethanol, vacuum filtering again, and collecting the aramid nanofibers; repeating step (c) multiple times;

[0012] (d) The collected aramid nanofibers were dispersed in anhydrous ethanol to obtain an aramid nanofiber solution.

[0013] As an improvement, the temperature of ultrasonic cleaning in step (1) is 20-30°C, and the time of ultrasonic cleaning is 15-30 minutes; vacuum drying is adopted, the drying temperature is 45-60°C, and the drying time is 10-30 minutes.

[0014] As an improvement, the concentration of the aramid nanofiber solution in step (2) is 1.5-3 mg / mL.

[0015] As an improvement, the mass ratio of PPTA to KOH in step (a) is 1:(1-3).

[0016] As an improvement, in step (a), the mass volume ratio of PPTA to DMSO solution is 1 g: (400-600) ml, and the mass volume ratio of PPTA to deionized water is 1 g: (15-25) ml; in step (b), deionized water is continued to be added in an amount of 2-3 times the volume of the DMSO solution, and the stirring time is 2-4 h.

[0017] As an improvement, a filter membrane with a pore size of 0.22 µm is used in step (b) and step (c).

[0018] The second aspect of the present invention also provides a zinc metal material modified with an aramid nanofiber interface layer, which is prepared by the preparation method. The thickness of the aramid nanofiber interface layer is 1-3 µm, and the aramid nanofiber interface layer is a three-dimensional porous structure with abundant and uniform pores.

[0019] The third aspect of the present invention also provides an application of the zinc metal material modified with the aramid nanofiber interface layer as a negative electrode material for an aqueous zinc ion battery.

[0020] As an improvement, the aqueous zinc ion battery is a zinc-zinc symmetrical battery, which includes a zinc sheet positive electrode, a zinc sheet negative electrode, a ZnSO4 electrolyte and a glass fiber separator. The zinc sheet negative electrode is punched from a zinc metal material modified with an aramid nanofiber interface layer.

[0021] As an improvement, the aqueous zinc ion battery is obtained by the following steps: using a punching machine to punch the prepared zinc metal material modified with the aramid nanofiber interface layer into a pole piece with a diameter of 12 mm, and assembling it in the order of a negative electrode shell, a spring, a gasket, a negative electrode, a GF / D standard glass fiber separator, a positive electrode, a gasket, and a positive electrode shell, wherein 80-100µL of 2M ZnSO4 electrolyte is added to the separator, and a button battery packaging machine is used to package it into a button battery.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) When the zinc metal material modified with the aramid nanofiber interface layer of the present invention is used in a zinc-zinc symmetrical battery, the −2 、1 mAh cm −2 Under the test conditions, the stable cycle exceeded 2000 hours, which is more than 13 times the cycle life of the zinc-zinc symmetric battery using bare zinc electrodes (about 135 hours), showing excellent stability.

[0024] (2) The zinc metal material modified with the aramid nanofiber interface layer of the present invention is hydrophobic and can serve as a physical barrier to prevent direct contact between water in the electrolyte and the zinc negative electrode, thereby inhibiting the occurrence of water-induced side reactions such as corrosion, hydrogen evolution, and passivation, thereby achieving an improvement in the cycle performance of aqueous zinc ion batteries.

[0025] (3) The zinc metal material modified by the aramid nanofiber interface layer of the present invention has abundant nucleophilic carbonyl functional groups, which have high zinc affinity and can adjust the solvation configuration to accelerate the Zn 2+ desolvation, thereby enhancing its transport kinetics.

[0026] (4) The zinc metal material modified with the aramid nanofiber interface layer of the present invention has a three-dimensional nanoporous structure. The uniform pores formed by the interwoven and stacked fibers can serve as ion channels for the transmission of zinc ions, uniformize the flux of zinc ions, reduce the uneven deposition of zinc ions, and thus inhibit the formation and growth of zinc dendrites, thereby significantly extending the cycle life of the aqueous zinc ion battery.

[0027] (5) The present invention washes the aramid nanofibers with water and anhydrous ethanol for multiple times, removes the residual KOH solution by water washing, and removes the residual DMSO solution and water by anhydrous ethanol washing. Finally, the collected aramid nanofibers are dispersed in anhydrous ethanol to make the aramid nanofibers more evenly dispersed, ensuring that the aramid nanofiber solution can be evenly scraped onto the pretreated zinc foil. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is the contact angle of the bare zinc metal of Example 1;

[0029] Figure 2 The contact angle of the zinc metal material modified with the aramid nanofiber interface layer of Example 1 of the present invention;

[0030] Figure 3 This is a SEM image of the zinc metal material modified with the aramid nanofiber interface layer of Example 1 of the present invention;

[0031] Figure 4 The molecular formula and schematic diagram of the aramid nanofiber used in Example 1 of the present invention;

[0032] Figure 5 This is a statistical diagram of the diameter distribution of the aramid nanofibers used in Example 1 of the present invention;

[0033] Figure 6 This is a statistical diagram of the pore size distribution of the aramid nanofiber interface layer of Example 1 of the present invention;

[0034] Figure 7 This is an SEM image of the cross section of the zinc metal material modified with the aramid nanofiber interface layer of Example 1 of the present invention;

[0035] Figure 8 This is an optical top view comparison of the zinc metal material modified with the aramid nanofiber interface layer of Example 1 of the present invention and three groups of zinc metal materials modified with the aramid nanofiber interface layer that were not prepared according to the method of Example 1;

[0036] Figure 9 for Figure 8 Comparison of the bonding degree of two groups of zinc metal materials modified with aramid nanofiber interface layers;

[0037] Figure 10 Schematic diagram of the aramid nanofiber solution of Example 1 of the present invention;

[0038] Figure 11 XRD pattern of the zinc metal material modified with the aramid nanofiber interface layer according to Example 1 of the present invention;

[0039] Figure 12 This is a comparison chart of the symmetrical battery cycle stability test of bare zinc and the zinc metal material modified with the aramid nanofiber interface layer of the present invention. DETAILED DESCRIPTION

[0040] The following embodiments are further descriptions of the present invention to illustrate the technical content of the present invention, but the essential content of the present invention is not limited to the following embodiments. Ordinary technicians in this field can and should know that any simple changes or replacements based on the essential spirit of the present invention should fall within the scope of protection required by the present invention. Example 1

[0041] A method for preparing a zinc metal material modified with an aramid nanofiber interface layer comprises the following steps:

[0042] S1. Place 0.5 g PPTA (aramid nanofiber) and 0.75 g KOH in a beaker, add 250 mL DMSO solution and 10 mL deionized water, and stir magnetically for 12 h. After stirring, add 500 mL deionized water to the beaker and stir for 4 h.

[0043] S2. Filter the solution obtained in step S1 using a vacuum filtration device, and collect the dried aramid nanofibers from the filter membrane using a water filter membrane with a pore size of 0.22 μm;

[0044] S3. Completely dispersing the aramid nanofibers obtained in step S2 in deionized water, vacuum filtering through a water filter membrane with a pore size of 0.22 μm, collecting the dried aramid nanofibers from the filter paper, and then completely dispersing the aramid nanofibers in anhydrous ethanol. Vacuum filtering through a PVDF membrane with a pore size of 0.22 μm, and collecting the dried aramid nanofibers from the filter paper; repeat step S3 five times;

[0045] S4. Disperse the dried aramid nanofibers in 250 mL of anhydrous ethanol and standardize the solution to obtain an aramid nanofiber solution with a concentration of 2 mg / mL. The obtained aramid nanofiber solution is as follows: Figure 10 As shown, it is light yellow;

[0046] S5. Place the cut commercial zinc foil in a beaker filled with sufficient anhydrous ethanol, place it in an ultrasonic cleaner, and ultrasonically clean it at 25°C for 30 minutes. Then, place it in a vacuum drying oven with a preset temperature of 45°C and dry it for 30 minutes.

[0047] S6. Use a scraper to evenly apply the aramid nanofiber solution obtained in step S4 on the pretreated zinc foil, place it in a ventilated place to dry, and after the solvent is completely evaporated, obtain a zinc metal material with an aramid nanofiber interface layer modified on the surface.

[0048] Figure 1 The contact angle of the bare zinc electrode is 85.2°. Figure 2 The contact angle of the zinc metal material modified with the aramid nanofiber interface layer (AANF@Zn) was tested to be 110.2°. It can be concluded that compared with bare zinc, the zinc metal material modified with the aramid nanofiber interface layer is hydrophobic, which can act as a physical barrier to prevent water molecules in the electrolyte from directly contacting the zinc metal, thereby inhibiting the occurrence of water-induced side reactions such as corrosion, hydrogen evolution, and passivation.

[0049] Figure 3 This is an SEM image of a zinc metal material modified with an aramid nanofiber interface layer. It can be seen that the interface layer is formed by interweaving and stacking aramid nanofibers, which has abundant and uniform pores. These pores can serve as uniform channels for the transmission of zinc ions. The uniform channels promote the uniform flux of zinc ion transport, thereby making the zinc ions uniformly deposited, avoiding the uneven tip effect caused by uneven zinc ion deposition, and effectively inhibiting the formation and growth of zinc dendrites.

[0050] Figure 4 It is the molecular formula and schematic diagram of aramid nanofiber. As can be seen from its molecular formula, aramid nanofiber has abundant nucleophilic carbonyl functional groups, which have high zinc affinity and can adjust the solvation configuration to accelerate Zn 2+ desolvation, thereby enhancing its transport kinetics.

[0051] Figure 5 This is the statistical distribution diagram of the diameter of aramid nanofibers. The average diameter of the fiber is 14.1 nm. Figure 6 This is a statistical distribution diagram of the pore size of the aramid nanofiber interface modification layer. It can be seen from the figure that the interface layer has a uniform pore size.

[0052] Figure 7 This is an SEM image of the cross-section of a zinc metal material modified with an aramid nanofiber interface layer. The thickness of the aramid nanofiber interface layer is 2.2 µm. It has strong adhesion to the zinc metal, is tightly bonded, and is not easy to fall off. The aramid nanofiber interface layer is formed by interwoven and stacked fibers, so it exhibits a three-dimensional porous structure with abundant and uniform pores.

[0053] Figure 8These are optical top-view comparisons of the zinc metal material modified with the aramid nanofiber interface layer of Example 1 of the present invention and three groups of zinc metal materials modified with the aramid nanofiber interface layer not prepared according to the method of Example 1; wherein, a is obtained by directly dispersing the aramid nanofibers in deionized water without washing; b is obtained by directly dispersing the aramid nanofibers in anhydrous ethanol without washing; c is obtained by dispersing the aramid nanofibers in deionized water after five cycles of washing (first with deionized water, then with anhydrous ethanol); and d is obtained by dispersing the aramid nanofibers in anhydrous ethanol after five cycles of washing (first with deionized water, then with anhydrous ethanol) (i.e., using the method of Example 1).

[0054] Then, referring to the method described in existing literature, the zinc metal with the aramid nanofiber interface layer is folded and unfolded, and then the zinc metal is bent again and restored. The adhesion between the aramid nanofiber interface layer and the zinc metal is determined by the integrity of the aramid nanofiber interface layer.

[0055] Combine Figure 8 Comparing images a and c, and b and d, shows that the performance of the aramid nanofiber interface layer modified zinc metal material prepared after washing is improved. Furthermore, a comparison between images c and d shows that the fiber distribution on the aramid nanofiber interface layer modified zinc metal material (AANF@Zn) prepared by dispersing the aramid nanofibers in anhydrous ethanol is more uniform, with no fiber agglomeration on the surface. However, the fiber distribution on the aramid nanofiber interface layer modified zinc metal material (WANF@Zn) prepared by dispersing the aramid nanofibers in deionized water is uneven, with significant agglomeration.

[0056] Figure 9 yes Figure 8 Comparison of the bonding degree between the two groups of aramid nanofiber interface layers and zinc metal materials ( Figure 9 (1) Correspondence Figure 8 Middle d, Figure 9 (2) Correspondence Figure 8 As shown in figure c, after folding and unfolding, the aramid nanofiber interface layer in figure d is tightly bonded to the zinc metal and does not fall off, while the aramid nanofiber interface layer in figure c falls off. The two are then bent and restored, and the aramid nanofiber interface layer in figure d is still tightly bonded to the zinc metal material and does not fall off, while the aramid nanofiber interface layer in figure c falls off further, indicating that the aramid nanofiber interface layer prepared by the present invention is tightly bonded to the zinc metal material and is not easy to fall off.

[0057] Figure 11 This is the XRD pattern of the zinc metal material modified with the aramid nanofiber interface layer, which is consistent with the standard PDF card of zinc metal, indicating that the addition of the interface layer has no effect on the zinc metal. Example 2

[0058] A method for preparing a zinc metal material modified with an aramid nanofiber interface layer comprises the following steps:

[0059] S1. Place 0.5 g PPTA and 0.75 g KOH in a beaker, add 300 mL DMSO solution and 12.5 mL deionized water, and stir magnetically for 10 h. After stirring, add 750 mL deionized water to the beaker and stir for 2 h.

[0060] S2. Filter the solution obtained in step S1 using a vacuum filtration device, and collect the dried aramid nanofibers from the filter membrane using a water filter membrane with a pore size of 0.22 μm;

[0061] S3. The aramid nanofibers obtained in step S2 are completely dispersed in deionized water, vacuum filtered using a water filter membrane with a pore size of 0.22 μm, and the dried aramid nanofibers are collected from the filter paper. The aramid nanofibers are then completely dispersed in anhydrous ethanol, and vacuum filtered using a PVDF membrane with a pore size of 0.22 μm, and the dried aramid nanofibers are collected from the filter paper. Step S3 is repeated four times.

[0062] S4, dispersing the drained aramid nanofibers in 250 mL of anhydrous ethanol and calibrating the solution to obtain an aramid nanofiber solution with a concentration of 2 mg / mL;

[0063] S5. Place the cut commercial zinc foil in a beaker filled with sufficient anhydrous ethanol, place it in an ultrasonic cleaner, and ultrasonically clean it at 20°C for 20 minutes. Then, place it in a vacuum drying oven with a preset temperature of 50°C and dry it for 30 minutes.

[0064] S6. Use a scraper to evenly apply the aramid nanofiber solution obtained in step S4 on the pretreated zinc foil, place it in a ventilated place to dry, and after the solvent is completely evaporated, obtain a zinc metal material with an aramid nanofiber interface layer modified on the surface. Example 3

[0065] A method for preparing a zinc metal material modified with an aramid nanofiber interface layer comprises the following steps:

[0066] S1. Place 0.5 g PPTA and 1 g KOH in a beaker, add 250 mL DMSO solution and 7.5 mL deionized water, and stir magnetically for 12 h. After stirring, add 500 mL deionized water to the beaker and stir for 3 h.

[0067] S2. Filter the solution obtained in step S1 using a vacuum filtration device, and collect the dried aramid nanofibers from the filter membrane using a water filter membrane with a pore size of 0.22 μm;

[0068] S3. Completely dispersing the aramid nanofibers obtained in step S2 in deionized water, vacuum filtering through a water filter membrane with a pore size of 0.22 μm, collecting the dried aramid nanofibers from the filter paper, and then completely dispersing the aramid nanofibers in anhydrous ethanol. Vacuum filtering through a PVDF membrane with a pore size of 0.22 μm, and collecting the dried aramid nanofibers from the filter paper; repeat step S3 six times;

[0069] S4, dispersing the drained aramid nanofibers in 250 mL of anhydrous ethanol and calibrating the solution to obtain an aramid nanofiber solution with a concentration of 2 mg / mL;

[0070] S5. Place the cut commercial zinc foil in a beaker filled with sufficient anhydrous ethanol, place it in an ultrasonic cleaner, and ultrasonically clean it at 30°C for 20 minutes. Then, place it in a vacuum drying oven with a preset temperature of 55°C and dry it for 20 minutes.

[0071] S6. Use a scraper to evenly apply the aramid nanofiber solution obtained in step S4 on the pretreated zinc foil, place it in a ventilated place to dry, and after the solvent is completely evaporated, obtain a zinc metal material with an aramid nanofiber interface layer modified on the surface. Example 4

[0072] A zinc-zinc symmetrical battery was prepared by using the zinc metal material modified with the aramid nanofiber interface layer prepared in Example 1 as the negative electrode, comprising the following steps:

[0073] The prepared zinc metal material modified with the aramid nanofiber interface layer was punched into electrodes with a diameter of 12 mm using a punching machine. The electrodes were assembled in the order of negative electrode shell, spring, 0.5 mm gasket, negative electrode, GF / D standard glass fiber separator, positive electrode, 0.5 mm gasket, and positive electrode shell. 90 μL of 2M ZnSO4 electrolyte was added to the separator, and the electrodes were packaged into button batteries using a button battery packaging machine.

[0074] Figure 12 It is a symmetrical button cell battery composed of a bare zinc electrode and a zinc metal anode modified with an aramid nanofiber interface layer. −2 The areal current density and 1 mAh cm −2The comparison chart of cycle performance under the surface capacity test conditions shows that the life of the button symmetrical battery using bare zinc electrode is about 135 hours, which is much shorter than the 2100 hours of the present invention, indicating that zinc metal does show excellent cycle stability after being modified with aramid nanofiber interface layer.

[0075] The present invention isolates the direct contact between water molecules and zinc metal by constructing a hydrophobic, zinc-philic, three-dimensional porous interface layer, thereby enhancing the Zn 2+ The transport kinetics and uniform zinc ion flux can reduce the occurrence of water-induced side reactions, inhibit the formation and growth of zinc dendrites, and make zinc metal materials show excellent stability, which has great development potential and application prospects.

[0076] It should be noted that the above-described embodiments of the present invention are merely explanations and clarifications for enabling those skilled in the art to understand the technical essence of the present invention. Therefore, the technical contents described are not intended to limit the substantial protection scope of the present invention. The substantial protection scope of the present invention shall be subject to the claims. Those skilled in the art should be aware that any modifications, equivalent substitutions, and improvements based on the substantial spirit of the present invention shall fall within the substantial protection scope of the present invention.

Claims

1. A method for preparing a zinc metal material modified with an aramid nanofiber interface layer, characterized in that: The following steps are involved: (1) Using anhydrous ethanol to clean the surface of the zinc foil by ultrasonic cleaning and drying to obtain a pretreated zinc foil; (2) evenly coating the aramid nanofiber solution on the pretreated zinc foil and drying it under ventilation to obtain a zinc metal material with an aramid nanofiber interface layer modified on the surface, wherein the zinc metal material modified with the aramid nanofiber interface layer has hydrophobicity; The aramid nanofiber solution is prepared by the following steps: (a) Place PPTA and KOH in a beaker, add DMSO solution and deionized water, and stir. (b) Deionized water is added continuously with stirring, and the stirred solution is filtered to collect the aramid nanofibers; (c) dispersing the aramid nanofibers in deionized water, vacuum filtering, collecting the aramid nanofibers, and redispersing them in anhydrous ethanol, vacuum filtering again, and collecting the aramid nanofibers; repeating step (c) multiple times; (d) The collected aramid nanofibers were dispersed in anhydrous ethanol to obtain an aramid nanofiber solution.

2. The method for preparing a zinc metal material modified with an aramid nanofiber interface layer according to claim 1, characterized in that: In the step (1), the ultrasonic cleaning temperature is 20-30°C, and the ultrasonic cleaning time is 15-30 min; vacuum drying is adopted, the drying temperature is 45-60°C, and the drying time is 10-30 min.

3. The method for preparing a zinc metal material modified with an aramid nanofiber interface layer according to claim 1, characterized in that: The concentration of the aramid nanofiber solution in step (2) is 1.5-3 mg / mL.

4. The method for preparing a zinc metal material modified with an aramid nanofiber interface layer according to claim 1, characterized in that: The mass ratio of PPTA to KOH in the step (a) is 1:(1-3).

5. The method for preparing a zinc metal material modified with an aramid nanofiber interface layer according to claim 1 or 4, characterized in that: In step (a), the mass volume ratio of PPTA to DMSO solution is 1 g: (400-600) ml, and the mass volume ratio of PPTA to deionized water is 1 g: (15-25) ml; in step (b), deionized water is added in an amount of 2-3 times the volume of the DMSO solution, and the stirring time is 2-4 hours.

6. The method for preparing a zinc metal material modified with an aramid nanofiber interface layer according to claim 1, characterized in that: In the steps (b) and (c), a filter membrane with a pore size of 0.22 μm is used.

7. A zinc metal material modified with an aramid nanofiber interface layer, characterized in that: The aramid nanofiber interface layer is prepared by the preparation method according to any one of claims 1 to 6, wherein the thickness of the aramid nanofiber interface layer is 1-3µm, and the aramid nanofiber interface layer is a three-dimensional porous structure with abundant and uniform pores.

8. Use of the zinc metal material modified with the aramid nanofiber interface layer according to claim 7 as a negative electrode material for aqueous zinc ion batteries, characterized in that: The aqueous zinc ion battery is a zinc-zinc symmetrical battery, which includes a zinc sheet positive electrode, a zinc sheet negative electrode, a ZnSO4 electrolyte and a glass fiber separator, wherein the zinc sheet negative electrode is punched from a zinc metal material modified with an aramid nanofiber interface layer; The aqueous zinc-ion battery is obtained by the following steps: using a punching machine to punch out the prepared zinc metal material modified with the aramid nanofiber interface layer into a pole piece with a diameter of 12 mm, and assembling it in the order of a negative electrode shell, a spring, a gasket, a negative electrode, a GF / D standard glass fiber separator, a positive electrode, a gasket, and a positive electrode shell, wherein 80-100 μL of 2M ZnSO4 electrolyte is added to the separator, and the battery is packaged into a button battery using a button battery packaging machine.

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