Zinc negative electrode with artificial lithium tantalate protection layer and preparation method and application thereof

Abstract

The invention relates to a zinc negative electrode with a lithium tantalate artificial protection layer and a preparation method and application thereof, and belongs to the technical field of aqueous zinc ion battery materials. The preparation method of the zinc negative electrode with the lithium tantalate artificial protection layer comprises the following steps: S1, adding lithium tantalate powder and polyvinylidene fluoride into a solvent, mixing, and magnetically stirring to prepare slurry; and S2, uniformly coating the slurry on the surface of a metal zinc substrate to form a lithium tantalate artificial protection layer, and drying to obtain the lithium tantalate artificial protection layer. The protective layer provided by the invention can regulate and control an interface electric field through a ferroelectric polarization effect, promote uniform zinc deposition and inhibit dendritic crystal growth; the high ionic conductivity is beneficial to improving mass transfer kinetics and relieving concentration polarization; meanwhile, the Ta-O site has good zinc affinity, nucleation sites are increased, and the electrochemical inertness can inhibit the side reaction of a water system. The zinc negative electrode modified by the protective layer shows excellent cycling stability and rate capability, and is suitable for a high-energy-density aqueous zinc ion battery.

Description

Technical Field

[0001] This application relates to the field of aqueous zinc-ion battery materials technology, and in particular to a zinc anode with an artificial protective layer of lithium tantalate, its preparation method and application. Background Technology

[0002] Lithium-ion batteries have long dominated the energy storage market due to their high energy density and mature industrial system. However, traditional lithium-ion batteries generally use organic electrolytes, which pose safety hazards, high production costs, and environmental sensitivity. In contrast, aqueous zinc-ion batteries, with their advantages of low cost, environmental friendliness, and high safety, are considered ideal candidates for the next generation of large-scale energy storage systems. Zinc foil can be used directly as the negative electrode material, effectively simplifying the battery structure and reducing manufacturing costs; meanwhile, aqueous electrolytes have high ionic conductivity and excellent operational safety. However, aqueous systems also face new challenges: the electrolyte voltage window is narrow, making it prone to side reactions such as hydrogen evolution and oxygen evolution at high temperatures or potentials; uneven zinc deposition can easily lead to dendrite growth, causing internal short circuits and the formation of "dead zinc," thus significantly shortening battery life. To achieve high energy density in aqueous zinc batteries, the zinc negative electrode needs to also have a high areal capacity (≥4 mAh cm⁻¹). -2 High coulombic efficiency and stable cycle performance are desirable features. However, slow interfacial mass transfer and uneven electric field distribution often lead to the formation of local zinc ion depletion regions. Once the critical sand capacity is reached, the rapid consumption of zinc ions at the interface induces disordered dendrite growth and interface passivation, thereby limiting the actual energy output and cycle life of the battery.

[0003] Currently, constructing an artificial protective layer for the zinc anode is considered one of the most effective strategies to address the aforementioned problems. An ideal artificial protective layer should meet the following characteristics: (1) possessing electronic insulation to achieve controllable uniform deposition beneath the layer; (2) having high ionic conductivity to ensure efficient zinc ion migration; and (3) possessing excellent chemical and electrochemical stability to effectively isolate active water molecules and suppress side reactions. Therefore, developing a novel artificial interface protective layer that can simultaneously regulate the interfacial electric field and suppress side reactions is of significant scientific and engineering application value for improving the cycle stability of the zinc anode and realizing the industrialization of aqueous zinc-ion batteries. Summary of the Invention

[0004] In view of this, this application provides a zinc anode with an artificial protective layer of lithium tantalate, its preparation method and application. The artificial protective layer has electronic insulation, ionic conductivity, ferroelectricity and zinc affinity, which can realize the regulation of the interfacial electric field and suppress dendrite growth and side reactions, thereby improving the cycle life and coulombic efficiency of the battery. It can effectively solve the problems of dendrite growth, hydrogen evolution and corrosion that easily occur in the zinc anode of existing aqueous zinc-ion batteries during charging and discharging.

[0005] The first aspect of this application provides a method for preparing a zinc anode with an artificial protective layer of lithium tantalate, comprising the following steps:

[0006] S1. Lithium tantalate powder and polyvinylidene fluoride are added to a solvent and mixed, and magnetically stirred to obtain a slurry.

[0007] S2. The slurry is uniformly coated on the surface of a zinc substrate to form an artificial protective layer of lithium tantalate. After drying, a zinc anode with an artificial protective layer of lithium tantalate is obtained.

[0008] Preferably, in step S1, the preparation process of the lithium tantalate powder is as follows: tantalum pentoxide and lithium carbonate are mixed, with an excess of 3-5% lithium carbonate to compensate for the volatilization of lithium during calcination, to obtain a mixture. The mixture is then wet-milled for 2-4 hours and calcined at 850-1000℃ for 6 hours to obtain lithium tantalate powder with a particle size of 500-800 nm, preferably at 950℃.

[0009] Preferably, in step S1, the mass ratio of lithium tantalate powder to polyvinylidene fluoride is 7:3 to 20:1, more preferably 9:1. Specifically, in step S1, the stirring time is 6 to 8 hours.

[0010] Preferably, in step S1, the solvent is dimethylpyrrolidone (NMP).

[0011] Preferably, in step S2, the thickness of the lithium tantalate artificial protective layer is 5~15 μm. More preferably, it is 10 μm.

[0012] Preferably, in step S2, the coating process is as follows: a 100μm coating applicator is used for scraping.

[0013] Preferably, in step S2, the drying temperature is 80 ℃ and the drying time is 8~10 h.

[0014] Preferably, in step S2, the zinc substrate is a zinc foil with a purity of not less than 99.9% and a thickness of 30~100 μm.

[0015] The second aspect of this application also provides a zinc anode with an artificial protective layer of lithium tantalate prepared by the above method.

[0016] Specifically, this application provides a zinc anode with a lithium tantalate artificial protective layer, comprising a metallic zinc substrate and an artificial protective layer formed on the surface of the zinc substrate. The artificial protective layer is composed of inorganic filler lithium tantalate (LiTaO3) and polyvinylidene fluoride (PVDF) binder. This artificial protective layer can achieve the dual functions of interfacial electric field regulation and side reaction suppression during battery charging and discharging, effectively inhibiting the growth of zinc dendrites and mitigating the occurrence of side reactions, thereby significantly improving the cycle stability and electrochemical performance of the zinc anode.

[0017] A third aspect of this application also provides an aqueous zinc-ion battery, comprising a positive electrode, a negative electrode, and an electrolyte; the negative electrode is the aforementioned zinc negative electrode with a lithium tantalate artificial protective layer; the electrolyte is selected from at least one of zinc sulfate aqueous solution, zinc chloride aqueous solution, and zinc trifluoromethanesulfonate aqueous solution, and the concentration of the electrolyte is 1~3 mol / L, and the amount added is 60~100 μL. This zinc negative electrode with a lithium tantalate artificial protective layer is assembled with a vanadium-based positive electrode to form a zinc-vanadium full cell, or with the same negative electrode to form a zinc symmetric cell.

[0018] Compared with the prior art, this application has the following advantages:

[0019] (1) Spontaneous polarization electric field regulates the distribution of interface electric field and inhibits dendrite growth: Lithium tantalate (LiTaO3) is a typical ferroelectric material with spontaneous polarization characteristics. Under the action of an external electric field, it can generate polarization electric fields with opposite directions, thereby regulating the distribution of interface electric field, weakening the local tip effect, and inhibiting the formation and uneven deposition of zinc dendrites.

[0020] (2) Zinc affinity promotes uniform nucleation and parallel deposition: The Ta-O bond sites on the surface of lithium tantalate have good zinc affinity properties, which can be used as nucleation active sites, refine the nucleation size, increase the nucleation density, promote the uniform nucleation and parallel orientation deposition of zinc ions, thereby effectively improving the deposition morphology of the negative electrode.

[0021] (3) Electrochemical inertness inhibits side reactions and improves interface stability: The electronic insulation of lithium tantalate in the artificial protective layer helps zinc ions pass through the coating to achieve controllable under-layer deposition. At the same time, it isolates active water molecules in the electrolyte, inhibits hydrogen evolution reaction and corrosion side reactions, thereby improving the stability and cycle life of the negative electrode interface.

[0022] (4) High ionic conductivity improves mass transfer kinetics and alleviates concentration polarization: Compared with traditional ferroelectric materials, lithium tantalate has higher ionic conductivity and lower zinc ion migration barrier, which can effectively improve the transport rate of zinc ions at the interface, alleviate concentration polarization, improve Sand capacity, and achieve high discharge depth and excellent rate performance.

[0023] (5) This application achieves multiple synergistic effects of interfacial electric field modulation, dendrite and side reaction suppression, and ion transport enhancement by constructing an artificial protective layer based on lithium tantalate on the surface of the zinc anode. The resulting zinc anode exhibits high specific capacity, excellent cycle stability, and rate performance. The preparation method of this application is simple, low-cost, and highly reproducible, and has good prospects for industrial application. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 The X-ray diffraction (XRD) pattern of the lithium tantalate powder prepared in Example 1 of this application;

[0026] Figure 2 The image shows a scanning electron microscope (SEM) image of the ferroelectric ceramic lithium tantalate prepared in Example 1 of this application and its corresponding elemental distribution (EDS mapping) spectrum.

[0027] Figure 3 A zinc-symmetric cell assembled from a zinc anode with an artificial lithium tantalate protective layer prepared in Example 1 of this application and a bare zinc anode in Comparative Example 1, at a current density of 1~40 mA cm⁻¹ -2 , with a capacity of 1 mAh cm -2 Ratio performance diagram under the given conditions;

[0028] Figure 4 A zinc-symmetric battery assembled from the zinc anode with an artificial lithium tantalate protective layer prepared in Example 1 of this application and the bare zinc anode in Comparative Example 1, at a current density of 1 mA cm⁻¹ -2 , with a capacity of 5 mAh cm -2 Cyclic performance graph under the given conditions;

[0029] Figure 5 The zinc anode with an artificial lithium tantalate protective layer, prepared in Example 1 of this application, was used to assemble a zinc symmetric cell at a current density of 1 mA cm⁻¹. -2 , with a capacity of 1 mAh cm -2 Under the condition of 50 h of cycling and 50 h of rest, the cycle-rest performance diagram is shown.

[0030] Figure 6 A zinc-symmetric battery assembled from the zinc anode with an artificial lithium tantalate protective layer prepared in Example 1 of this application and the bare zinc anode in Comparative Example 1, at a current density of 1 mA cm⁻¹ -2 , with a capacity of 1 mAh cm -2 SEM comparison images of zinc anode after 2000h cycling under the specified conditions;

[0031] Figure 7 The zinc-vanadium full cell assembled from the zinc anode with an artificial lithium tantalate protective layer prepared in Example 1 of this application and the bare zinc anode in Comparative Example 1, at a current density of 5 A g, is shown to be... -1Cyclic performance diagram under low positive electrode active mass loading;

[0032] Figure 8 The zinc-vanadium full cell assembled from the zinc anode with an artificial lithium tantalate protective layer prepared in Example 1 of this application and the bare zinc anode in Comparative Example 1, at a current density of 3 A g, is shown to be... -1 Cyclic performance diagram under high positive electrode activity mass loading. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] Unless otherwise specified, the experimental methods used in the embodiments of this application are all conventional methods.

[0035] In the following examples and comparative examples, unless otherwise specified, all raw materials can be prepared by commercial purchase or conventional methods.

[0036] Example 1

[0037] This embodiment provides a method for preparing a zinc anode with an artificial protective layer of lithium tantalate and its electrochemical performance testing. The specific steps are as follows:

[0038] (1) Synthesis of lithium tantalate powder: 4.2621 g of tantalum pentoxide (Ta2O5) and 0.7379 g of lithium carbonate (Li2CO3) were weighed, with lithium element in excess at 3% based on the stoichiometric ratio to compensate for the loss of lithium element due to volatilization during calcination. The raw materials were placed in a mortar, and an appropriate amount of anhydrous ethanol was added as a dispersion medium. The mixture was thoroughly ground for 4 h to achieve uniform mixing. The mixed slurry was then dried, and the resulting dry powder was placed in an alumina crucible. Under an air atmosphere, the temperature was raised to 950 °C in a muffle furnace at a heating rate of 5 °C / min, and calcined at this temperature for 6 h. After calcination, the powder was cooled, removed, and ground into a fine powder to obtain lithium tantalate (LiTaO3) powder with a particle size of approximately 500~800 nm.

[0039] (2) Preparation of zinc anode with lithium tantalate artificial protective layer: Weigh 0.01 g of polyvinylidene fluoride (PVDF) into a weighing bottle, add an appropriate amount of dimethylpyrrolidone (NMP) dropwise, and stir magnetically for 30 min to obtain a uniform and transparent solution. Then add 0.09 g of lithium tantalate powder and continue to stir magnetically for 6 h to obtain a uniform white slurry. Take a 30 μm thick zinc foil and place it on a glass plate. Clean the surface with lint-free paper dipped in anhydrous ethanol. Coat the slurry evenly onto the zinc foil surface (coating thickness 100 μm). Dry in an oven at 80 ℃ for 10 h to remove the solvent to obtain a zinc anode with a lithium tantalate artificial protective layer of about 10 μm thickness (denoted as LTO@Zn).

[0040] (3) Preparation of electrolyte: Dissolve zinc sulfate heptahydrate (ZnSO4·7H2O) in deionized water to prepare a 2 mol / L zinc sulfate electrolyte.

[0041] (4) Preparation of the positive electrode: Weigh 0.01 g of PVDF and add an appropriate amount of NMP, stir magnetically for 30 min to obtain a uniform and transparent solution. Add 0.07 g of ammonium vanadate (NH4V4O) 10 The NVO4 and 0.02 g conductive carbon black were mixed and ground for 30 min, then added to the above PVDF solution and magnetically stirred for 6 h to obtain a uniform black slurry. The slurry was uniformly coated onto a stainless steel mesh current collector and dried in an oven at 80 ℃ for 10 h to obtain the NVO4 positive electrode sheet.

[0042] (5) Assembly and testing of half-cells and full-cells: In the symmetric cell test, the prepared LTO@Zn negative electrode was cut into 1.13 cm pieces. 2 The circular wafers serve as the positive and negative electrodes of the symmetrical battery. The CR2032 coin cell is assembled in the following order: negative electrode casing - gasket - spring contact - negative electrode (LTO@Zn) - glass fiber separator - positive electrode (LTO@Zn) - positive electrode casing. Cycle performance testing conditions include: 1 mA cm⁻¹ -2 / 5 mAh cm -2 1 mA cm -2 / 1 mAh cm -2 With 1~40 mA cm -2 / 1 mAh cm -2 In the full-cell test, a full cell was assembled using an LTO@Zn anode and an NVO cathode, with current densities of 5 A g. -1 and 3 A g -1 Perform cyclic performance testing.

[0043] Example 2

[0044] Lithium tantalate material was prepared by solid-state reaction according to the method described in Example 1, and a slurry of lithium tantalate and PVDF was prepared at a mass ratio of 20:1. The preparation conditions were the same as in Example 1. A zinc anode with an artificial protective layer of LTO@Zn and a thickness of approximately 10 μm was finally obtained. A symmetric cell assembled using this anode achieved a performance of 1 mA cm⁻¹. -2 / 1 mAh cm -2 Under all conditions, it can be stably cycled for approximately 1500 hours.

[0045] Example 3

[0046] Lithium tantalate was synthesized via a solid-state reaction method as described in Example 1. Lithium tantalate and PVDF were mixed at a mass ratio of 8:2 to prepare a homogeneous slurry. The slurry was coated onto a 30 μm thick zinc foil and dried at 80 °C for 10 h to obtain an LTO@Zn anode with a thickness of approximately 10 μm. A symmetric cell assembled using this anode operated at 1 mA cm⁻¹. -2 / 1 mAh cm -2 Under all conditions, it can be stably cycled for approximately 2200 hours.

[0047] Comparative Example 1

[0048] Take a 30 μm thick zinc foil, clean the surface with lint-free paper soaked in anhydrous ethanol, without applying any coating, and cut it into pieces with an area of ​​1.13 cm². 2 The discs (denoted as Bare Zn) serve as the positive and negative electrodes of the symmetrical battery. The CR2032 coin cell is assembled in the following order: negative electrode casing - gasket - spring contact - negative electrode (Bare Zn) - glass fiber separator - positive electrode (Bare Zn) - positive electrode casing. Cyclic performance test conditions include: 1 mA cm⁻¹ -2 / 5 mAh cm -2 1 mA cm -2 / 1 mAh cm -2 With 1~40 mA cm -2 / 1 mAh cm -2 Meanwhile, a full cell was assembled using this bare zinc anode and an NVO cathode, and measured at 5 A g. -1 and 3 A g -1 Cyclic performance testing was conducted under the specified conditions.

[0049] Test case

[0050] Figure 1 This is the X-ray diffraction (XRD) pattern of the ferroelectric ceramic lithium tantalate prepared in Example 1 of this application. Figure 1 It can be seen that the diffraction characteristic peaks of lithium tantalate (LiTaO3) are consistent with the data of the standard PDF card, indicating that lithium tantalate powder with a complete crystal structure was successfully synthesized by solid-state reaction method.

[0051] Figure 2 This image shows a scanning electron microscope (SEM) image of the ferroelectric ceramic lithium tantalate prepared in Example 1 of this application, along with its corresponding elemental distribution (EDS mapping) spectrum. Figure 2 It can be seen that the prepared lithium tantalate particles have a particle size of about 500~800 nm, and the Ta and O elements are uniformly distributed inside the particles.

[0052] Figure 3 A zinc-symmetric cell assembled from a zinc anode with an artificial lithium tantalate protective layer prepared according to Example 1 of this application and a bare zinc anode from Comparative Example 1 is used at 1~40 mA cm⁻¹. -2 Rate performance graph over the current density range. (From...) Figure 3 It can be seen that the symmetrical cell with LTO@Zn anode can cycle stably under different current densities without short circuit or significant fluctuations in polarization voltage. This indicates that the artificial protective layer can regulate the zinc ion transport behavior at the interface, reduce concentration polarization under high current density, delay the formation of ion depletion region, and thus suppress dendrite growth. In contrast, the symmetrical cell with bare zinc anode experienced a short circuit at about 60 h, showing obvious interface instability.

[0053] Figure 4 A zinc-symmetric cell assembled with a zinc anode having an artificial lithium tantalate protective layer prepared according to Example 1 of this application and a bare zinc anode from Comparative Example 1 is used at 1 mA cm⁻¹. -2 Current density, 5 mAh cm -2 Cycling performance graph under discharge capacity conditions (corresponding to 28.5% depth of discharge). (From...) Figure 4 It is known that under these conditions, the symmetric cell using LTO@Zn anode can cycle stably for about 1000 h, indicating that the lithium tantalate artificial protective layer still has a good interface regulation effect at high discharge depths, which can significantly improve the stability of the anode. In contrast, the bare zinc symmetric cell experienced a short circuit after about 100 h.

[0054] Figure 5 A zinc-symmetric cell assembled with a zinc anode having an artificial lithium tantalate protective layer prepared according to Example 1 of this application and a bare zinc anode from Comparative Example 1 is used at 1 mA cm⁻¹. -2 Current density, 1 mAh cm -2 Cycle-rest performance graph after 25 cycles at capacity, followed by a 50-hour rest period and re-cycle. The symmetrical cell using LTO@Zn anode maintains a stable voltage plateau after multiple charge-discharge cycles and long-term rest, indicating that the artificial protective layer effectively inhibits interfacial corrosion and side reactions, improving the reversibility of the zinc anode.

[0055] Zinc symmetric cells assembled with a zinc anode having an artificial lithium tantalate protective layer prepared according to Example 1 of this application and a bare zinc anode from Comparative Example 1 were tested at a current density of 1 mA cm⁻¹. -2 , with a capacity of 1 mAh cm -2 After 2000 hours of cycling under the specified conditions, the electrode was disassembled. SEM analysis was performed on the zinc anode, as shown... Figure 6 As shown, in Example 1, the LTO@Zn anode surface is smooth and flat, exhibiting a large area of ​​parallel (002) crystal plane deposition morphology, with no obvious dendrites or byproducts observed, indicating that the lithium tantalate artificial protective layer can effectively inhibit zinc dendrite growth and slow down side reactions. In contrast, the bare zinc anode surface in Comparative Example 1 is rough and has obvious dendrites, indicating severe interface corrosion.

[0056] Figure 7 A zinc-vanadium full cell was assembled from a zinc anode with an artificial lithium tantalate protective layer prepared according to Example 1 of this application and a bare zinc anode from Comparative Example 1 at 5 A g. -1 At current density, low positive electrode active mass loading (1.36 mg cm⁻¹) -2 Cyclic performance diagram under the given conditions. (From...) Figure 7 It can be seen that the zinc-vanadium battery using LTO@Zn anode still maintains a discharge specific capacity of approximately 174 mAh g after 1000 charge-discharge cycles. -1 This indicates that the zinc anode with an artificial protective layer of lithium tantalate exhibits good interfacial stability. The zinc-vanadium full cell using bare zinc as the anode experienced a short circuit after 400 cycles due to interface deterioration.

[0057] Figure 8 A zinc-vanadium full cell was assembled from a zinc anode with an artificial lithium tantalate protective layer prepared according to Example 1 of this application and a bare zinc anode from Comparative Example 1 at 3 A g. -1 High positive electrode active mass loading (16.29 mg cm⁻¹) at current density -2 Cyclic performance diagram under the given conditions. (From...) Figure 8 As can be seen, the battery retained 89% of its capacity after 400 cycles, further verifying the interfacial stability of the lithium tantalate artificial protective layer under high load conditions. In contrast, the battery using a bare zinc anode experienced a short circuit after approximately 100 cycles due to interfacial deterioration.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for producing a zinc negative electrode having a lithium tantalate artificial protective layer, characterized by, The method comprises the following steps: S1, mixing lithium tantalate powder and polyvinylidene fluoride in a solvent, and stirring magnetically to prepare a slurry; S2, uniformly coating the slurry on the surface of a zinc metal substrate to form a lithium tantalate artificial protective layer, and drying to obtain a zinc negative electrode with a lithium tantalate artificial protective layer.

2. The method for producing a zinc negative electrode having a lithium tantalate artificial protective layer according to claim 1, characterized by, In step S1, the lithium tantalate powder is prepared by mixing tantalum pentoxide and lithium carbonate, wherein the amount of lithium carbonate is 3-5% in excess, obtaining a mixture, wet-milling the mixture for 2-4 hours, and calcining at 850-1000℃ for 6 hours to obtain lithium tantalate powder with a particle size of 500-800 nm.

3. The method for producing a zinc negative electrode having a lithium tantalate artificial protective layer according to claim 1, characterized by, In step S1, the mass ratio of lithium tantalate powder to polyvinylidene fluoride is 7:3-20:

1.

4. The method for producing a zinc negative electrode having a lithium tantalate artificial protective layer according to claim 1, characterized by, In step S1, the solvent is dimethylpyrrolidone NMP.

5. The method of producing a zinc negative electrode with a lithium tantalate artificial protective layer according to claim 1, characterized by, In step S2, the thickness of the lithium tantalate artificial protective layer is 5-15 μm.

6. The method of producing a zinc negative electrode with a lithium tantalate artificial protective layer according to claim 1, characterized by, In step S2, the coating process is scraping with a 100 μm film applicator.

7. The method of producing a zinc negative electrode having a lithium tantalate artificial protective layer according to claim 1, characterized by, In step S2, the drying temperature is 80℃, and the drying time is 8-10 hours.

8. The method for producing a zinc negative electrode having a lithium tantalate artificial protective layer according to claim 1, characterized by, In step S2, the zinc metal substrate is a zinc foil with a purity of not less than 99.9%.

9. A zinc negative electrode with a lithium tantalate artificial protective layer prepared by the method of any one of claims 1-8.

10. An aqueous zinc-ion battery, characterized in that, The battery comprises a positive electrode, a negative electrode, and an electrolyte; the negative electrode is the zinc negative electrode with a lithium tantalate artificial protective layer of claim 9; the electrolyte is selected from at least one of zinc sulfate aqueous solution, zinc chloride aqueous solution, and zinc trifluoromethane sulfonate aqueous solution, and the concentration of the electrolyte is 1-3 mol / L.

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