Flake-like nanoporous Zn / Cu / Al2Cu alloy electrode, preparation method and application thereof

Abstract

This disclosure provides a nanoporous Zn / Cu / Al2Cu alloy electrode with a lamellar structure, its preparation method, and its applications. The core-shell structure of the nanoporous Zn / Cu / Al2Cu alloy electrode with a lamellar structure consists of an incompletely corroded Al2Cu core and a fully corroded Cu shell. The Al phase, which originally alternated with the Al2Cu phase in the eutectic alloy, is dealloyed to form lamellar macroporous channels. Both the Cu / Al2Cu alloy ligaments of the lamellar macroporous channels and the lamellar macroporous channels themselves have a certain thickness, and the Zn replaced on the surface serves as the initial circulating zinc source. The nanoporous Zn / Cu / Al2Cu alloy electrode with a lamellar structure provided in this disclosure has an electrical couple composed of an Al2Cu core and a Cu shell with different electrode potentials. This allows for a highly reversible zinc stripping / electroplating process while reducing the nucleation overpotential and local current density. Compared to pure zinc metal anodes, symmetrical cells and aqueous zinc-ion full cells prepared using layered nanoporous Zn / Cu / Al2Cu alloy electrodes exhibit higher electrochemical activity and structural stability.

Description

Technical Field

[0001] This disclosure relates to the field of aqueous zinc-ion battery electrode materials, and more particularly to the field of nanoporous Zn / Cu / Al2Cu alloy electrode technology with a layered structure. Background Technology

[0002] With the continuous adjustment of the energy system, the storage and conversion of renewable energy has attracted widespread attention. Developing convenient, controllable, and sustainable energy storage technologies to compensate for the intermittency and uncontrollability of renewable energy is an urgent priority. Compared with other energy storage technologies, lithium-ion batteries dominate large-scale energy storage systems due to their longer cycle life and higher energy density. However, the rising raw material prices of lithium-ion battery components, limited lithium resource reserves, and safety issues caused by organic electrolytes severely limit their further development, forcing the development of more promising next-generation energy storage systems. Aqueous multivalent metal-ion batteries have attracted much attention due to their inherent high safety, excellent ionic conductivity, good thermal stability, and higher cycle performance. Compared with other aqueous systems, aqueous zinc-ion batteries, with their moderate redox potential (-0.76V vs SHE), high elemental abundance, and excellent theoretical capacity, have attracted great interest.

[0003] Thanks to the high safety offered by aqueous electrolytes, zinc-ion batteries, which are insensitive to oxygen and moisture, can be assembled directly in air, greatly simplifying the assembly process and effectively reducing manufacturing costs. Furthermore, the direct application of metallic zinc in aqueous electrolytes not only utilizes its high theoretical capacity (720 mAh g⁻¹) but also... -1 ) and volumetric capacity (5855mAh cm⁻¹) -3 The advantages of zinc-ion batteries, and their intrinsic stability in aqueous solutions, make long-term stable cycling possible. The working principle of zinc-ion batteries is similar to that of lithium-ion batteries. Inspired by the lithium-ion battery system, a series of feasible positive electrode materials for aqueous zinc-ion batteries have been developed, including manganese-based oxides, vanadium-based oxides, Prussian blue analogs, cobalt-based phosphates, polyanionic compounds, and organic compounds. These materials have shown excellent stability in aqueous electrolytes. However, aqueous zinc-ion batteries commonly use zinc foil as the negative electrode. The undesirable side reactions generated during repeated stripping / electroplating inevitably lead to a decline in battery performance, making it unsuitable for practical applications. The high reactivity of zinc with aqueous solutions during cycling, resulting in dendrite growth, surface corrosion, passivation, and hydrogen evolution, are the main causes of zinc negative electrode instability and battery failure. Therefore, establishing an efficient and stable zinc stripping / electroplating process is crucial to improving its performance.

[0004] A layered, large-channel porous alloy electrode is obtained by chemically dealloying an aluminum-copper eutectic alloy over a controlled time. This structure maintains good machinability. The resulting three-dimensional porous structure not only significantly increases the electrode's specific surface area, thereby reducing the local current density and nucleation overpotential for ion deposition, but also creates abundant local galvanic couples within the alloy due to the different electrode potentials between the incompletely corroded Al₂Cu intermetallic compound phase and the metallic Cu phase obtained during dealloying. This effectively guides reversible and dendrite-free zinc stripping / electroplating behavior. The synergistic effect of different potential phases and the porous structure makes it possible to mass-produce zinc-ion battery anodes that can achieve long-term stable cycling. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, this disclosure provides a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure, its preparation method, and its application.

[0006] According to a first aspect of this disclosure, a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure is provided, characterized in that...

[0007] The core-shell structure of the nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure consists of an Al2Cu core that is not completely corroded inside and a Cu shell that is completely corroded on the surface.

[0008] In eutectic alloys, the Al phase, which originally alternated with the Al2Cu phase, forms layered macroporous channels after dealloying.

[0009] Both the Cu / Al2Cu alloy ligament of the lamellar macroporous channel and the lamellar macroporous channel have a certain thickness, and the Zn replaced on the surface serves as the initial circulating zinc source.

[0010] Preferably, the thickness of the Cu / Al2Cu alloy ligament is 500 nm, and the thickness of the layered macroporous channel is 300 nm.

[0011] According to a second aspect of this disclosure, a method for preparing a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure is provided, characterized in that...

[0012] 1) Determine the Cu-Al ratio according to the eutectic point, weigh out pure copper ingots and pure aluminum ingots respectively, and remove the surface oxide layer;

[0013] 2) Place the copper ingot in a corundum crucible, put it into a nitrogen-protected melting furnace, and melt it at a certain melting temperature and keep it warm.

[0014] 3) After confirming that the copper ingot has completely melted, add the aluminum ingot, continue to keep it at this temperature, and stir gently to ensure that the two metals are completely dissolved and fully mixed into a metal mixture;

[0015] 4) Pour the high-temperature liquid metal mixture into a mold, ensuring that the metal mixture solidifies into a metal block at an appropriate cooling rate;

[0016] 5) Cut the completely cooled metal block into 200-300μm thick metal sheets on an electrical discharge wire cutting machine, and grind off the oxide layer on the surface.

[0017] 6) The metal sheet is placed in an HCl solution for chemical dealloying to prepare a Cu / Al2Cu alloy electrode with a layered nanoporous structure with a thickness of ~100μm.

[0018] 7) The dealloyed Cu / Al2Cu alloy electrode is placed in a zinc immersion solution containing Zn(NO3)3 and NaOH to obtain a nanoporous Zn / Cu / Al2Cu alloy electrode with surface-displaced zinc as the initial circulating zinc source.

[0019] Preferably, the melting temperature in step 2) is 900-1400℃, and the holding time is 1-2 hours;

[0020] Preferably, the heat preservation time in step 3) is 0.5-1.5 hours;

[0021] Preferably, the cooling rate in step 4) is 100 K s. -1 ;

[0022] Preferably, in step 6), the metal sheet is chemically de-alloyed in an HCl solution, wherein the concentration of the de-alloying HCl solution is 1 mol / L. -1 The corrosion time is 1 hour;

[0023] Preferably, the concentration of Zn(NO3)3 in the zinc immersion solution in step 7) is 0.15 mol / L. -1 The concentration of NaOH is 2 mol / L. -1 The replacement time is 3 minutes.

[0024] According to a third aspect of this disclosure, an application of a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure is provided, characterized in that...

[0025] An aqueous zinc-ion battery was constructed using the nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure as the negative electrode of the aqueous zinc-ion battery.

[0026] The beneficial effects of this disclosure are:

[0027] The nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure disclosed herein has an electrical couple consisting of an Al2Cu core and a Cu shell with different electrode potentials. This enables a highly reversible zinc stripping / electroplating process while reducing the nucleation overpotential and local current density. Compared to pure zinc metal anodes, symmetric cells and aqueous zinc-ion full cells prepared using the layered nanoporous Zn / Cu / Al2Cu alloy electrode exhibit higher electrochemical activity and structural stability. Attached Figure Description

[0028] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. The drawings are provided for a better understanding of the present invention and are not intended to limit the scope of this disclosure. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0029] Figure 1 Field emission (FESEM) image of a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure;

[0030] Figure 2 XRD pattern of nanoporous Zn / Cu / Al2Cu alloy electrode with layered structure;

[0031] Figure 3 EDS spectrum of nanoporous Zn / Cu / Al2Cu alloy electrode with layered structure;

[0032] Figure 4 A schematic diagram of the preparation process of a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure;

[0033] Figure 5 Nucleation overpotential curves (time-voltage curves) of nanoporous Zn / Cu / Al2Cu alloy electrodes with layered structures;

[0034] Figure 6 A standard symmetrical cell composed of a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure operates at 0.5 mA cm⁻¹. -2 Graph of constant current charge-discharge test (voltage-time curve) under current density for 4000h;

[0035] Figure 7 Electrochemical impedance spectroscopy (EIS) diagram of a standard symmetrical cell composed of a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure;

[0036] Figure 8 Nanoporous Zn / Cu / Al2Cu alloy electrodes with layered structures and Zn supported on carbon cloth 0.12A standard aqueous zinc-ion full cell, constructed with a V₂O₅ electrode, operates at 0.2 mV s⁻¹. -1 Cyclic voltammetry (CV) test results;

[0037] Figure 9 Nanoporous Zn / Cu / Al2Cu alloy electrodes with layered structures and Zn supported on carbon cloth 0.12 Electrochemical impedance (EIS) spectra of a standard aqueous zinc-ion full cell with a V2O5 electrode in the frequency range of 100 kHz to 10 mHz.

[0038] Figure 10 Nanoporous Zn / Cu / Al2Cu alloy electrodes with layered structures and Zn supported on carbon cloth 0.12 A standard aqueous zinc-ion full cell with a V₂O₅ electrode is constructed at 0.5 Ag. -1 Cyclic stability test results at current density;

[0039] Figure 11 Nanoporous Zn / Cu / Al2Cu alloy electrodes with layered structures and Zn supported on carbon cloth 0.12 A standard aqueous zinc-ion full cell with a V₂O₅ electrode is constructed at 10 Ag. -1 Cyclic stability test results at current density;

[0040] Figure 12 Nanoporous Zn / Cu / Al2Cu alloy electrodes with layered structures and Zn supported on carbon cloth 0.12 V₂O₅ electrodes form standard aqueous zinc-ion full cells in the range of 0.2-10 Ag. -1 The graph shows the rate performance test conducted at the specified current density. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0042] Example 1

[0043] The preparation method of the nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure disclosed herein is as follows:

[0044] A. Weigh 760g of pure aluminum ingot (Al, purity 99.99%) and 243g of pure copper ingot (Cu, purity 99.99%), and remove the surface oxide layer;

[0045] B. Place the copper ingot in a corundum crucible and put it into a nitrogen-protected smelting furnace, heat it to 900°C and hold it for 1 hour.

[0046] C. After confirming that the copper ingot has completely melted, add the aluminum ingot and continue to keep it at 900°C for 0.5 hours, stirring gently to ensure that the two metals are completely dissolved and fully mixed into a metal mixture.

[0047] D. Pour the high-temperature liquid metal mixture into the heat-insulating iron mold, ensuring the metal mixture maintains a temperature of 100 Ks. -1 The cooling rate solidifies it into a metal block;

[0048] E. Cut the completely cooled metal block into 200-300μm thick metal sheets on an electrical discharge wire cutting machine, and grind off the oxide layer on the surface.

[0049] F. Place the metal sheet in a 1M HCl solution for 1 hour to corrode it;

[0050] G. The dealloyed porous Cu / Al2Cu alloy electrode is placed in a zinc immersion solution containing 0.15M Zn(NO3)3 and 2M NaOH for 3 minutes to obtain a nanoporous Zn / Cu / Al2Cu alloy electrode with surface-displaced zinc as the initial circulating zinc source. This electrode can be used as the negative electrode of an aqueous zinc-ion battery.

[0051] Example 2

[0052] The preparation process of the nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure disclosed herein is as follows:

[0053] A. Weigh 760g of pure aluminum ingot (Al, purity 99.99%) and 243g of pure copper ingot (Cu, purity 99.99%), and remove the surface oxide layer;

[0054] B. Place the copper ingot in a corundum crucible and put it into a nitrogen-protected smelting furnace, heat it to 1300°C and hold it for 1.5 hours.

[0055] C. After confirming that the copper ingot has completely melted, add the aluminum ingot and continue to keep it at 1300℃ for 1 hour, stirring gently to ensure that the two metals are completely dissolved and fully mixed into a metal mixture.

[0056] D. Pour the high-temperature liquid metal mixture into the heat-insulating iron mold, ensuring the metal mixture maintains a temperature of 100 Ks. -1 The cooling rate solidifies it into a metal block;

[0057] E. Cut the completely cooled metal block into 200-300μm thick metal sheets on an electrical discharge wire cutting machine, and grind off the oxide layer on the surface.

[0058] F. Place the metal sheet in a 1M HCl solution for 2 hours to corrode it;

[0059] G. Place the dealloyed porous Cu electrode in an electroplating solution containing 1M ZnSO4 and electroplat at -0.05V for 3 minutes to obtain a nanoporous Zn / Cu electrode, which can be used as the negative electrode of an aqueous zinc-ion battery.

[0060] Example 3

[0061] The preparation process of the nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure disclosed herein is as follows:

[0062] A. Weigh 760g of pure aluminum ingot (Al, purity 99.99%) and 243g of pure copper ingot (Cu, purity 99.99%), and remove the surface oxide layer;

[0063] B. Place the copper ingot in a corundum crucible and put it into a nitrogen-protected smelting furnace, heat it to 1400°C and hold it for 2 hours.

[0064] C. After confirming that the copper ingot has completely melted, add the aluminum ingot and continue to keep it at 1400℃ for 1.5 hours, stirring gently to ensure that the two metals are completely dissolved and fully mixed into a metal mixture.

[0065] D. Pour the high-temperature liquid metal mixture into the heat-insulating iron mold, ensuring the metal mixture maintains a temperature of 100 Ks. -1 The cooling rate solidifies it into a metal block;

[0066] E. Cut the completely cooled metal block into 200-300μm thick metal sheets on an electrical discharge wire cutting machine, and grind off the oxide layer on the surface.

[0067] F. Place the metal sheet in a 1M HCl solution for corrosion for 3 hours;

[0068] G. The dealloyed porous Cu / Al2Cu alloy electrode is placed in a zinc immersion solution containing 0.15M Zn(NO3)3 and 2M NaOH for 3 minutes to obtain a nanoporous Zn / Cu / Al2Cu alloy electrode with surface-displaced zinc as the initial circulating zinc source. This electrode can be used as the negative electrode of an aqueous zinc-ion battery.

[0069] XRD analysis confirmed that the aluminum-copper eutectic alloy with controlled etching time of 1 hour formed a Cu / Al2Cu core-shell structure, while the aluminum-copper eutectic alloy with controlled etching time of 4 hours formed a porous Cu structure.

[0070] Taking Example 1 as an example, the morphology and structure characterization of the material and the electrochemical performance characterization results are further compared.

[0071] (1) Characterization of the morphology and structure of the material.

[0072] Field emission microscopy (FESEM) characterization revealed that the Zn / Cu / Al2Cu alloy electrode, after dealloying and replacement of the zinc source, exhibited a layered nanoporous structure, such as... Figure 1 This demonstrates that the alloy electrode sample has a lamellar porous structure with a ligament size of 500 nm and a lamellar macropore channel size of 300 nm. Field emission scanning electron microscopy (FE-SEM) further confirms that the Zn layer was successfully replaced on the alloy surface obtained in this disclosure, and the presence of Al proves the successful retention of the internal intermetallic compound Al₂Cu.

[0073] Figure 2 The XRD pattern of a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure shows that, apart from the presence of a small number of characteristic peaks of the Al phase that is not completely corroded, the coexistence of the Zn, Al2Cu and Cu phases is demonstrated.

[0074] Figure 3 The EDS spectra of nanoporous Zn / Cu / Al2Cu with a layered structure are shown in Table 1.

[0075] element Wt% At% Zn 71.0 61.0 Cu 19.8 16.5 Al 6.5 13.1 O 2.7 9.4

[0076] Table 1

[0077] The results demonstrate that the lamellar nanoporous alloy sample has a core-shell structure consisting of a Cu shell and an Al2Cu core, while the presence of a large amount of Zn confirms the successful replacement of residual Al on the surface after controlled-time corrosion.

[0078] The electrode fabrication process in this disclosure is as follows: Figure 4 As shown, the eutectic alloy ingot obtained by melting in a high-temperature furnace is in 1 mol L -1 Layered nanoporous alloy electrodes are obtained by controlling time corrosion in hydrochloric acid solution to facilitate subsequent electrochemical performance testing.

[0079] (2) Results of electrochemical performance characterization of materials.

[0080] The nanoporous Zn / Cu / / Al2Cu alloy sheet with a layered structure prepared in Example 1 was cut into electrode sheets, and then the alloy electrode sheet was used as the working electrode with 1 mol L... -1 Zn(OTf)2 was used as the solute and a mixture of diethylene glycol and dimethyl ether in a volume ratio of 2:1 with water was used as the solution to form an electrolyte, and a standard symmetrical cell was constructed for electrochemical testing.

[0081] The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure prepared in Example 1 was subjected to an amplitude of 0.5 mA cm⁻¹. -2 Nucleation overpotential was tested at current density (time-voltage curve).

[0082] The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure prepared in Example 1 was used to assemble a symmetrical cell at 0.5 mA cm⁻¹. -2 The current density was subjected to a 4000-hour constant current charge-discharge test (voltage-time curve).

[0083] The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure prepared in Example 1 was used to assemble a symmetrical cell, and electrochemical impedance spectroscopy (EIS) was performed in the frequency range of 100 kHz to 10 mHz.

[0084] The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure from Example 1 was used as the negative electrode of the battery, with Zn supported on carbon cloth. 0.12 V₂O₅ electrode is used as the positive electrode of the battery, 1 mol L -1 Zn(OTf)2 was used as the solute and a mixture of diethylene glycol and dimethyl ether in a volume ratio of 2:1 with water was used as the solution to form an electrolyte, and a standard aqueous zinc-ion full cell was constructed for electrochemical testing.

[0085] The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure prepared in Example 1 was combined with Zn supported on carbon cloth. 0.12 A standard aqueous zinc-ion full cell composed of V₂O₅ electrodes was placed at 0.2 mV s⁻¹. -1 Cyclic voltammetry (CV) tests were performed at a scan rate of [missing value].

[0086] The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure prepared in Example 1 was combined with Zn supported on carbon cloth. 0.12 A standard aqueous zinc-ion full cell composed of V2O5 electrodes was subjected to electrochemical impedance spectroscopy (EIS) testing in the frequency range of 100 kHz to 10 mHz.

[0087] The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure prepared in Example 1 was combined with Zn supported on carbon cloth. 0.12 A standard aqueous zinc-ion full cell composed of V₂O₅ electrodes was placed in a 0.5Ag atmosphere. -1 Cyclic stability tests were conducted for 200 cycles at a given current density.

[0088] Figure 5In the time-voltage curves, the nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure exhibits a nucleation overpotential of only ~2.2 mV, confirming that the excellent zinc affinity of the alloy electrode in this disclosure effectively reduces the energy barrier during electrochemical plating, thereby effectively improving its electrochemical performance. Figure 6 The test results of the symmetric cell show that the symmetric cell with the nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure can achieve a 0.5 mA cm⁻¹ ampere-ampere ratio. -2 At current densities exceeding 4000 hours, no significant voltage hysteresis was observed. In contrast, pure zinc symmetric cells exhibited significant voltage hysteresis within a 200-hour testing period. Figure 7 The impedance of a pure zinc symmetric cell and a symmetric cell with a layered nanoporous Zn / Cu / / Al2Cu alloy electrode are compared. The charge transfer resistance of the symmetric cell with the layered nanoporous Zn / Cu / / Al2Cu alloy electrode is about 5Ω, while the charge transfer resistance of the pure zinc symmetric cell is about 635Ω. This demonstrates that the layered nanoporous Zn / Cu / / Al2Cu alloy electrode has stronger electrochemical activity than pure zinc foil. Figure 8 It is a nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure and Zn supported on carbon cloth. 0.12 An aqueous zinc-ion battery with a V₂O₅ electrode achieves a voltage range of 0.4–1.4 V with a current of 0.2 mV / s. -1 The CV test curves were obtained using the scan rate. The reduction peaks of the battery redox curves appeared at 0.67V and 0.96V, respectively, while the oxidation peaks appeared at 0.79V and 1.10V, respectively. Figure 9 In the frequency range of 100kHz to 10mHz, nanoporous Zn / Cu / / Al2Cu alloy electrodes with a layered structure and pure zinc foil are respectively coated with Zn supported on carbon cloth. 0.12 A comparison of the electrochemical impedance spectroscopy (EIS) of aqueous zinc-ion full cells composed of V₂O₅ electrodes. From... Figure 9 As can be seen, the charge transfer resistance of the full cell assembled using alloy electrodes is only 5Ω, while the charge transfer resistance of the full cell using pure zinc foil as the negative electrode is as high as 90Ω. The low charge transfer resistance and the degree of polarization together demonstrate that the full cell assembled using alloy electrodes has excellent electrochemical activity. Figure 10 The nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure and the pure zinc electrode are respectively coated with Zn supported on carbon cloth. 0.12 A standard aqueous zinc-ion full cell was assembled using V₂O₅ as the positive electrode at a capacity of 0.5 A g. -1 Cyclic curves at current densities. From Figure 10As can be seen from the above, when a nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure is coupled with Zn supported on carbon cloth... 0.12 When a V₂O₅ electrode is used to form an aqueous zinc-ion full cell, its performance at 0.5 A g -1 It can still maintain more than 330 mAh g after cycling for 400 hours at a current density. -1 The specific capacity was [not specified]. In stark contrast, the aqueous zinc-ion full cell assembled with pure zinc sheet electrodes rapidly failed after only 50 hours of cycling, ultimately retaining only 100 mAh g⁻¹. -1 The specific capacity. This fully demonstrates the unique advantages of the unique internal structure of the alloy electrode in terms of the cycle stability of zinc-ion batteries. For example... Figure 11 As shown, thanks to the porous structure's ability to significantly reduce local current density and regulate ion flux, the alloy electrode exhibits a significant advantage in high current density, particularly at 10Ag. -1 It still retains more than 235mAh g after 5000 stable cycles at high current density. -1 The specific capacity confirms its excellent rate performance. Figure 12 It is a nanoporous Zn / Cu / / Al2Cu alloy electrode with a layered structure and Zn supported on carbon cloth. 0.12 V₂O₅ electrodes form standard aqueous zinc-ion full cells in the range of 0.2-10 Ag. -1 Rate performance tests were conducted at current densities ranging from 0.2 Ag. -1 Increase to 10A g -1 At this time, the battery can retain more than 50% of its capacity, demonstrating its excellent rate performance. All the above performance tests show that, compared to pure zinc metal anodes, symmetric batteries and aqueous zinc-ion full batteries prepared using nanoporous Zn / Cu / / Al2Cu alloy electrodes with a layered porous structure exhibit higher electrochemical activity and structural stability, showing promising application prospects in the field of aqueous batteries. The method disclosed in this paper can also be extended to other energy storage battery systems, providing new methods and ideas for improving the electrochemical activity and structural stability of metal electrodes.

Claims

1. A nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure, characterized in that, The core-shell structure of the nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure consists of an Al2Cu core that is not completely corroded inside and a Cu shell that is completely corroded on the surface. In eutectic alloys, the Al phase, which originally alternated with the Al2Cu phase, forms lamellar macroporous channels after dealloying. Both the Cu / Al2Cu alloy ligament of the lamellar macroporous channel and the lamellar macroporous channel have a certain thickness, and the Zn replaced on the surface serves as the initial circulating zinc source.

2. The nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure as described in claim 1, characterized in that, The Cu / Al2Cu alloy ligament has a thickness of 500 nm, and the lamellar macroporous channel has a thickness of 300 nm.

3. The method for preparing a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure as described in claim 1 or 2, characterized in that, 1) Determine the Cu-Al ratio according to the eutectic point, weigh out pure copper ingots and pure aluminum ingots respectively, and remove the surface oxide layer; 2) Place the copper ingot in a corundum crucible, put it into a nitrogen-protected melting furnace, and melt it at a certain melting temperature and keep it warm. 3) After confirming that the copper ingot has completely melted, add the aluminum ingot, continue to keep it at this temperature, and stir gently to ensure that the two metals are completely dissolved and fully mixed into a metal mixture; 4) Pour the high-temperature liquid metal mixture into a mold, ensuring that the metal mixture solidifies into a metal block at an appropriate cooling rate; 5) Cut the completely cooled metal block into 200-300μm thick metal sheets on an electrical discharge wire cutting machine, and grind off the oxide layer on the surface. 6) The metal sheet is placed in an HCl solution for chemical dealloying to prepare a Cu / Al2Cu alloy electrode with a layered nanoporous structure with a thickness of ~100μm. 7) Place the Cu / Al2Cu alloy electrode after dealloying in step 6) into a zinc immersion solution containing Zn(NO3)3 and NaOH to obtain a nanoporous Zn / Cu / Al2Cu alloy electrode with surface-displaced zinc as the initial circulating zinc source.

4. The method for preparing a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure according to claim 3, characterized in that, The melting temperature in step 2) is 900-1400℃.

5. The method for preparing a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure according to claim 3, characterized in that, Continue to maintain this temperature for 0.5-1.5 hours as described in step 3).

6. The method for preparing a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure according to claim 3, characterized in that, The cooling rate in step 4) is 100 K s. -1 .

7. The method of producing a nanoporous Zn / Cu / Al2Cu alloy electrode having a flake-like structure according to claim 3, characterized by, The concentration of the HCI solution of step 6) is 1 mol L -1 with a corrosion time of 1 hour.

8. The method for preparing a nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure according to claim 3, characterized in that, The concentration of Zn(NO3)3 in the zinc immersion solution in step 7) is 0.15 mol / L. -1 The concentration of NaOH is 2 mol / L. -1 The replacement time is 3 minutes.

9. The application of the nanoporous Zn / Cu / Al2Cu alloy electrode with a layered structure as described in claim 1 or 2, characterized in that: A water-based zinc-ion battery was constructed by using the nanoporous Zn / Cu / Al2Cu alloy electrode with the layered structure as the negative electrode of the water-based zinc-ion battery.

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