Three-dimensional nano-array zinc negative electrode material and preparation method and application thereof

Abstract

The application provides a three-dimensional nano-array zinc negative electrode material and a preparation method and application thereof, and relates to the technical field of zinc negative electrode materials.The three-dimensional nano-array zinc negative electrode material comprises a foamed copper base, a CuO nanowire array and metal zinc nanosheets, the CuO nanowire array is uniformly grown on the foamed copper base, and the metal zinc nanosheets are uniformly coated on the outer surfaces of the CuO nanowires.The three-dimensional nano-array zinc negative electrode material can inhibit the zinc negative electrode dendrite growth of ZIBs in the charging and discharging process, and has excellent electrochemical performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of zinc negative electrode materials, in particular to a three-dimensional nano-array zinc negative electrode material and a preparation method and application thereof. BACKGROUND

[0002] With the development of economy, electric energy has become an indispensable material in people's life. Using wind energy, solar energy and tidal energy to generate electricity can greatly reduce the emission of greenhouse gases such as carbon dioxide, so converting wind energy, solar energy and tidal energy into electric energy has become a new green economic industry. However, wind energy, solar energy and tidal energy are uncontrollable due to the influence of nature, so the power grid using wind energy, solar energy and tidal energy to generate electricity has instability. Large-scale energy storage system (ESS) as an effective intermediate device can improve the reliability of the power grid by storing the electric energy generated by wind energy, solar energy and tidal energy before being integrated into the power system and then regulating the output.

[0003] The composition of the energy storage system cannot be separated from the energy storage device. Aqueous rechargeable zinc ion battery (ZIBs) has the advantages of non-flammability, environmental protection, abundant resources and low cost, and is a good energy storage device. The theoretical capacity of the zinc anode of aqueous zinc ion battery (AZIBs) is 820 mAh g -1 , and the electrochemical potential is low, which is -0.76 V compared with the standard hydrogen electrode. The safe aqueous electrolyte and abundant natural resources can meet the requirements of large-scale ESS.

[0004] However, during the charging and discharging process of ZIBs, uneven zinc deposition leads to the problem of zinc dendrite growth of the zinc negative electrode, which not only reduces the electrochemical reversibility of ZIBs, but also causes short circuit. Therefore, it is a technical problem that needs to be solved by those skilled in the art to provide a zinc negative electrode material capable of inhibiting zinc dendrite growth. SUMMARY

[0005] (I) Technical problems to be solved

[0006] In view of the deficiencies of the prior art, the present application provides a three-dimensional nano-array zinc negative electrode material and a preparation method and application thereof, which solves the problem of zinc dendrite growth of the zinc negative electrode during the charging and discharging process of ZIBs.

[0007] (II) Technical solutions

[0008] In order to achieve the above purpose, the present application is realized by the following technical solutions:

[0009] A three-dimensional nano-array zinc negative electrode material comprises a foam copper substrate, a CuO nanowire array and metal zinc nanosheets, the CuO nanowire array is uniformly grown on the foam copper substrate, and the metal zinc nanosheets are uniformly coated on the outer surfaces of the CuO nanowires.

[0010] In an embodiment, the CuO nanowire array has a length of 10-20 μm and a diameter of 100-150 nm.

[0011] In an embodiment, the metal zinc nanosheets are coated on the outer surfaces of the CuO nanowires by an electron beam deposition method.

[0012] In an embodiment, the metal zinc nanosheets have a thickness of 90-180 nm.

[0013] A preparation method of a three-dimensional nano-array zinc negative electrode material comprises the following steps:

[0014] (1) Foam copper cleaning:

[0015] The foam copper is sequentially placed in 1M hydrochloric acid solution, acetone and anhydrous ethanol, and is sequentially ultrasonically treated for 10-30 min;

[0016] (2) Preparation of CF@Cu(OH)2 nanowires:

[0017] A mixed solution of NaOH solution and ammonium persulfate solution is provided, the cleaned foam copper is reacted with the mixed solution, the obtained reaction product is cleaned with deionized water, and then is placed in a 50-70℃ oven for drying for 10-14 h to obtain CF@Cu(OH)2 nanowires;

[0018] (3) Preparation of CF@CuO nanowires:

[0019] The CF@Cu(OH)2 nanowires are high-temperature annealed to obtain CF@CuO nanowires;

[0020] (4) Preparation of CF@CuO@Zn three-dimensional nano-array zinc negative electrode material:

[0021] The CF@CuO nanowires are placed on a plating pan and are sent into a chamber of an electron beam coating instrument, are plated with zinc after vacuumizing, and are cooled after ending to obtain a CF@CuO@Zn three-dimensional nano-array zinc negative electrode material.

[0022] In an embodiment, the concentration of the NaOH solution in the step (2) is 4M, the concentration of the ammonium persulfate solution is 0.2M, the reaction temperature in the step (2) is room temperature, and the reaction time is 5-10 min.

[0023] In an embodiment, the temperature rising rate of the high-temperature annealing in step (3) is 60-90 DEG C / min, the high-temperature annealing temperature is 160-200 DEG C, and the high-temperature annealing time is 0.5-1.5 h.

[0024] In an embodiment, the vacuum degree of the electron beam evaporator cavity in step (4) is less than or equal to 1*10 -4 Pa, the reaction evaporation adjustment number is 8-9, the deposition rate is 0.3-0.6 angstrom / s, and the reaction time is 0.5-1 h.

[0025] In an embodiment, in S4, the CF@CuO@Zn three-dimensional nano array zinc negative electrode material is sealed and stored.

[0026] The three-dimensional nano array zinc negative electrode material and / or the three-dimensional nano array zinc negative electrode material prepared by the preparation method has an application in energy conversion and storage.

[0027] (Three) beneficial effects

[0028] The application provides a three-dimensional nano array zinc negative electrode material and a preparation method and application thereof.

[0029] The application discloses a three-dimensional nano array zinc negative electrode material, which comprises a foam copper substrate, a CuO nanowire array and a metal zinc nanosheet, the CuO nanowire array is uniformly grown on the foam copper substrate, and the metal zinc nanosheet is uniformly coated on the outer surface of the CuO nanowire. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed in the embodiments or prior art description. Obviously, the drawings described below are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0031] Figure 1 XRD pattern of the CF@CuO@Zn three-dimensional nanowire array zinc negative electrode material prepared for Example 3.

[0032] Figure 2 Scanning electron microscope pattern of the CF@CuO@Zn three-dimensional nanowire array prepared for Example 1.

[0033] Figure 3 Scanning electron microscope pattern of the CF@CuO@Zn three-dimensional nanowire array prepared for Example 2.

[0034] Figure 4 Scanning electron microscope pattern of the CF@CuO@Zn three-dimensional nanowire array prepared for Example 3.

[0035] Figure 5 Scanning electron microscope pattern of the CF@CuO@Zn three-dimensional nanowire array prepared for Example 4.

[0036] Figure 6 Comparison chart of electrochemical performance of the CF@CuO@Zn three-dimensional nanowire array zinc negative electrode material prepared for Example 3 and pure zinc foil;

[0037] 6a - Symmetric cycle curve chart of the electrode material at 2 mA cm -2 -2 under a current density of 1 mAh.

[0038] 6b - Symmetric rate curve chart of the electrode material at a current density of 0.5, 1, 2, 5, 10, 0.5 mA cm -2 -2.

[0039] Figure 7 Comparison chart of Tafel curves of the CF@CuO@Zn three-dimensional nanowire array zinc negative electrode material prepared for Example 3 and pure zinc foil. DETAILED DESCRIPTION

[0040] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0041] The embodiment of the present application provides a three-dimensional nano array zinc negative electrode material and a preparation method and application thereof, solves the problem that zinc negative electrode is prone to dendrite growth in the charging and discharging process of ZIBs, and inhibits the dendrite growth of the zinc negative electrode in the charging and discharging process of ZIBs.

[0042] The technical solutions in the embodiment of the present application are used to solve the above technical problems, and the general idea is as follows:

[0043] For pure zinc foil, zinc dendrites can pierce the glass fiber separator to cause short circuit of the battery. Preferential dissolution at the root of the dendrites can cause the dendrites to separate from the main body, thereby causing the “dead zinc” to be in an inactive state, thereby accelerating the consumption of zinc. In addition, the zinc negative electrode tends to become loose after repeated cycles due to its inherent unsupported nature, which can cause volume change of ZIBs.

[0044] In order to inhibit the formation of zinc dendrites, the prior art changes the anode, the electrolyte and the anode electrolyte interface, however, the ultra-high cost and the low ionic conductivity limit the application of electrolyte modification. The prior art also includes surface modification of the zinc negative electrode material, which can adjust nucleation and inhibit side reactions, but uncontrolled growth of dendrites will inevitably occur due to uneven deposition of zinc under the modified layer. Therefore, instead of changing the electrolyte and the anode electrolyte interface and surface modification, the present application provides a porous foam copper substrate, which can give the zinc negative electrode material dimensional stability, thereby avoiding rapid consumption of metal zinc and electrolyte due to uncontrollable shape change of the negative electrode material; in addition, the CuO nanowire array has uniform local electric field distribution, which provides uniform and abundant active sites for nucleation and growth of zinc in the charging and discharging process, that is, by adjusting the ion distribution, the zinc negative electrode is stabilized, and the growth of dendrites is inhibited. At the same time, the space inside the three-dimensional nano array can limit the growth of dendrites, thereby relieving the volume change of ZIBs, and by adjusting the three-dimensional nano array structure, the local electric field strength can be reduced, the uniform deposition of zinc in the charging and discharging process is realized, the growth of zinc dendrites is further inhibited, and in addition, by introducing the method of electron beam deposition, the zinc has a more uniform deposition morphology, which is beneficial to the deposition and stripping of zinc ions in the charging and discharging process.

[0045] In order to better understand the above technical solutions, the above technical solutions will be described in detail in combination with the drawings in the specification and specific embodiments.

[0046] Embodiment 1:

[0047] The embodiment provides a preparation method of a three-dimensional nano array zinc negative electrode material, comprising the following steps:

[0048] (1) Foam copper cleaning:

[0049] First, place the copper foam (2 cm × 3 cm) into 1 M hydrochloric acid, acetone and anhydrous ethanol respectively, and sonicate for 10 min in each.

[0050] (2) Preparation of CF@Cu(OH)2 nanowire samples:

[0051] Immerse the cleaned copper foam in a 20 mL beaker containing a mixed solution of 10 mL 4 M NaOH and 10 mL 0.2 M (NH4)2S2O8. React at room temperature for 5 min until a uniform dark blue product is formed on the surface of the copper foam. Remove the foam and rinse it several times with deionized water. Then place it in a vacuum oven and vacuum dry it at 50 °C for 10 h. Let it cool before use.

[0052] (3) Preparation of CF@CuO nanowire samples:

[0053] The CF@Cu(OH)2 nanowire samples were placed in a ceramic boat and sent into a muffle furnace. The temperature was increased to 180°C at a rate of 60°C per minute and held for annealing for 1 hour. The temperature was then decreased to room temperature at a rate of 60°C per minute and collected for later use.

[0054] (4) Preparation of CF@CuO@Zn samples:

[0055] The CF@CuO nanowire sample was attached to the coating tray and placed inside the electron beam coating instrument chamber. The chamber door was closed, and a vacuum was drawn until the vacuum level dropped to 1×10⁻⁶. -4 The coating process begins below Pa, with an evaporation adjustment number of 8, a deposition rate controlled at 0.3 Å / s, and a reaction time of 0.6 h. After the reaction is completed, the chamber is cooled for 2 h before sampling, thus obtaining the CF@CuO@Zn three-dimensional nanoarray zinc anode material.

[0056] according to Figure 2 The prepared CF@CuO@Zn three-dimensional nanoarray anode material was observed to include a CuO nanowire structure with zinc uniformly coated on the CuO nanowires. Pores between the different nanowires were clearly visible, and the overall nanoarray appeared slightly sparse. After assembling a symmetrical battery using this CF@CuO@Zn three-dimensional nanoarray zinc anode material, a performance of 2 mA cm⁻¹ was observed. -2 At a current density of 1 mAh, it cycles symmetrically for approximately 460 hours.

[0057] The prepared CF@CuO@Zn three-dimensional nanoarray anode material has a CuO nanowire array length of 10 μm, a diameter of 100 nm, and a zinc nanosheet thickness of 90 nm.

[0058] Example 2:

[0059] This embodiment provides a method for preparing a three-dimensional nanoarray zinc anode material, including the following steps:

[0060] (1) Foam copper cleaning:

[0061] Foam copper (2 cm x 3 cm) was placed in 1 M hydrochloric acid, acetone, and anhydrous ethanol, respectively, and was ultrasonically treated for 20 min.

[0062] (2) Preparation of CF@Cu(OH)2nanowire samples:

[0063] The cleaned foam copper was immersed in a beaker containing 20 mL of a mixed solution of 10 mL of 4 M NaOH and 10 mL of 0.2 M (NH4)2S2O8, and was reacted at room temperature for 5 min. After a uniform dark blue product was formed on the surface of the foam copper, the foam copper was taken out, washed several times with deionized water, and then vacuum dried at 60°C for 12 h. After cooling, the foam copper was reserved for use;

[0064] (3) Preparation of CF@CuO nanowire samples:

[0065] The CF@Cu(OH)2nanowire samples were placed in a porcelain boat and sent into a muffle furnace. The temperature was raised to 180°C at a rate of 80°C per minute, and then annealed for 1 h. After the temperature was lowered to room temperature at a rate of 80°C per minute, the samples were collected and reserved.

[0066] (4) Preparation of CF@CuO@Zn samples:

[0067] The CF@CuO nanowire samples were attached to a plating pan, and were placed in the cavity of an electron beam coating instrument. The door was closed, and vacuum was applied. When the vacuum degree was reduced to 1 x 10 -4 Pa, film coating was started. The evaporation adjustment number was 9, the deposition rate was controlled at 0.5 A / s, the reaction time was 0.7 h, and after the reaction was completed, the cavity was cooled for 4 h, and then the samples were taken, thereby obtaining the CF@CuO@Zn three-dimensional nanometer array zinc negative electrode material.

[0068] According to Figure 3 , it was observed that the CuO nanometer array structure of the CF@CuO@Zn three-dimensional nanometer array negative electrode material was stable, the zinc nanometer sheet completely and uniformly coated the CuO nanowire, the nanometer array as a whole was slightly dense, but the space between different nanowires was still visible. After the CF@CuO@Zn three-dimensional nanometer array zinc negative electrode material was used to assemble a symmetrical battery, the symmetrical cycle was about 1000 h at a current density of 2 mA cm -2 and a capacity of 1 mAh.

[0069] The CF@CuO@Zn three-dimensional nanometer array negative electrode material prepared had a CuO nanowire array length of 15 pm and a diameter of 125 nm, and a metal zinc nanometer sheet thickness of 120 nm.

[0070] Example 3

[0071] The embodiment provides a preparation method of a three-dimensional nano-array zinc negative electrode material, and comprises the following steps:

[0072] (1) Foam copper cleaning:

[0073] Firstly, foam copper (2 cm x 3 cm) is respectively placed in 1 M hydrochloric acid, acetone and anhydrous ethanol, and is sequentially ultrasonically treated for 30 min.

[0074] (2) Preparation of CF@Cu(OH)2 nanowire sample:

[0075] The cleaned foam copper is immersed into a beaker containing 20 mL of a mixed solution of 10 mL of 4 M NaOH and 10 mL of 0.2 M (NH4)2S2O8, and is reacted at room temperature for 5 min; after uniform deep blue product is generated on the surface of the foam copper, the foam copper is taken out, washed with deionized water for several times, and then vacuum dried at 70 DEG C for 14 h; after cooling, the foam copper is reserved;

[0076] (3) Preparation of CF@CuO nanowire sample:

[0077] The CF@Cu(OH)2 nanowire sample is placed into a porcelain boat and is sent into a muffle furnace, and is heated to 180 DEG C at a heating rate of 90 DEG C per minute, and is annealed for 1 h; after being cooled to room temperature at a cooling rate of 90 DEG C per minute, the sample is collected and reserved.

[0078] (4) Preparation of CF@CuO@Zn sample:

[0079] The CF@CuO nanowire sample is pasted on a plating pan, and is placed into a cavity of an electron beam coating instrument; the door is closed, and vacuum is extracted; after the vacuum degree is reduced to 1x10 -4 Pa, film coating is started, the evaporation adjustment number is 9, the deposition rate is controlled at 0.5 angstrom / s, the reaction time is 0.8 h, the cavity is cooled for 4 h after the reaction is completed, and then the sample is taken, so that the CF@CuO@Zn three-dimensional nano-array zinc negative electrode material is obtained.

[0080] According to Figure 4 , it is observed that the CuO nanowire array structure of the CF@CuO@Zn three-dimensional nano-array negative electrode material is stable, the zinc nanosheet completely and uniformly covers the CuO nanowire array, the zinc nanosheet structure is clear, and the overall morphology is more uniform, complete, dense and the like. After the CF@CuO@Zn three-dimensional nano-array zinc negative electrode material is used to assemble a symmetrical battery, the symmetrical cycle is about 1300 h under the current density of 2 mA cm -2 and the capacity of 1 mAh.

[0081] According to Figure 1The CF@CuO@Zn negative electrode material was subjected to XRD analysis to determine the phase structure thereof. As can be seen from the element peak distribution in the figure, the material is successfully prepared without other impurities.

[0082] The prepared CF@CuO@Zn three-dimensional nanoarray negative electrode material has CuO nanowire arrays with a length of 18 μm and a diameter of 140 nm, and the metal zinc nanosheet has a thickness of 150 nm.

[0083] Example 4

[0084] The embodiment provides a preparation method of a three-dimensional nanoarray zinc negative electrode material, comprising the following steps:

[0085] (1) Cleaning of the foam copper:

[0086] The foam copper (2 cm x 3 cm) is first placed in 1 M hydrochloric acid, acetone and anhydrous ethanol respectively, and is subjected to ultrasonic treatment for 20 min.

[0087] (2) Preparation of the CF@Cu(OH)2 nanowire sample:

[0088] The cleaned foam copper is immersed in a beaker containing 20 mL of a mixed solution of 10 mL of 4 M NaOH and 10 mL of 0.2 M (NH4)2S2O8, and is reacted at room temperature for 5 min. After a uniform dark blue product is generated on the surface of the foam copper, the foam copper is washed with deionized water for several times, and is then dried at 60°C under vacuum for 12 h. After cooling, the foam copper is reserved;

[0089] (3) Preparation of the CF@CuO nanowire sample:

[0090] The CF@Cu(OH)2 nanowire sample is placed in a porcelain boat and is sent into a muffle furnace. The temperature is raised at a rate of 60°C per minute to 180°C, and is maintained for 1 h. After the temperature is lowered to room temperature at a rate of 60°C per minute, the sample is collected and is reserved.

[0091] (4) Preparation of the CF@CuO@Zn sample:

[0092] The CF@CuO nanowire sample is attached to a plating pan, and is placed in the cavity of an electron beam coating instrument. The door is closed, and vacuumization is started. After the vacuum degree is reduced to 1 x 10 -4 Pa, film coating is started. The evaporation adjustment number is 9, the deposition rate is controlled at 0.5 Å / s, the reaction time is 1 h, and after the reaction is completed, the cavity is cooled for 3 h, and then the sample is taken, to obtain the CF@CuO@Zn three-dimensional nanoarray zinc negative electrode material.

[0093] According to Figure 5In the CF@CuO@Zn three-dimensional nanoarray anode material, a clear zinc nanosheet structure was observed, completely encapsulating the CuO nanowire array. The nanowire array exhibited denser interlacing, resulting in a compact overall morphology, although noticeable cracks were present. After assembling a symmetrical battery using this CF@CuO@Zn three-dimensional nanoarray zinc anode material, a performance of 2 mA cm⁻¹ was achieved. -2 At a current density of 1 mAh, it cycles symmetrically for approximately 1200 h.

[0094] The prepared CF@CuO@Zn three-dimensional nanoarray anode material has a CuO nanowire array length of 20 μm, a diameter of 150 nm, and a zinc nanosheet thickness of 180 nm.

[0095] The electrochemical performance of the prepared CF@CuO@Zn three-dimensional nanoarray zinc anode material was tested, and the results are as follows:

[0096] in, Figure 6 a is the electrode material prepared in Example 3, mixed with pure zinc foil at 2 mA cm⁻¹. -2 Symmetrical cycle curves of charge-discharge at 1mAh current density. Figure 6 b represents the electrode material prepared in Example 3, used in conjunction with pure zinc foil at current densities of 0.5, 1, 2, 5, 10, and 0.5 mA cm⁻¹. -2 The symmetrical ratio curve below, from Figure 6 The symmetrical cyclic curves in a show that the CF@CuO@Zn three-dimensional nanoarray zinc anode material operates at 2 mA cm⁻¹. -2 At the specified current density, the symmetrical charge-discharge cycle of 1mAh reaches 1300 hours, demonstrating excellent cycle performance compared to the initial pure zinc foil. Figure 6 As can be seen from the symmetry rate-of-capacity curve, the CF@CuO@Zn three-dimensional nanoarray zinc anode material exhibits stable symmetry rate-of-capacity performance at current densities of 0.5, 1, 2, 5, 10, and 0.5 mA cm⁻¹. -2 It has a lower and more stable overpotential.

[0097] in, Figure 7 This is a comparison of Tafel curves for the CF@CuO@Zn three-dimensional nanoarray zinc anode material prepared in Example 3 and pure zinc foil. From... Figure 7 It can be seen that, compared with the initial pure zinc foil, the CF@CuO@Zn three-dimensional nanoarray zinc anode material has a higher corrosion potential and a lower corrosion current, indicating that the corrosion trend is also suppressed.

[0098] The excellent electrochemical performance of the CF@CuO@Zn three-dimensional nanoarray zinc anode material is mainly attributed to the following factors:

[0099] Using copper foam as a substrate, its three-dimensional structure buffers volume changes and provides a copper source for the growth of CuO nanowires. CuO has a superior affinity for Zn, which can promote the uniform distribution of Zn during the nucleation process. At the same time, the formed nanoarray can provide a uniform local electric field distribution, providing abundant and uniform active sites for Zn nucleation and growth. In addition, the electron beam deposition method is more conducive to achieving uniform zinc deposition, thereby suppressing dendrite growth and achieving excellent electrochemical performance.

[0100] Secondly, this invention utilizes electron beam deposition to prepare a three-dimensional nanoarray zinc anode material, which exhibits excellent cycle performance, stable rate performance, lower overpotential, and suppresses dendrite growth and corrosion tendency.

[0101] Furthermore, this invention synthesizes a CF@CuO@Zn three-dimensional nanoarray anode current collector material using porous copper foam as a substrate through in-situ growth, annealing, and electron beam deposition. The raw materials, equipment, and processes used in this method are simple, low-cost, easy to operate, safe, non-toxic, harmless, clean, and environmentally friendly.

[0102] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0103] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention 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 of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A three-dimensional nanoarray zinc anode material, characterized in that, The invention comprises a copper foam substrate, a CuO nanowire array, and zinc nanosheets. The CuO nanowire array is uniformly grown on the copper foam substrate, and the zinc nanosheets are uniformly coated on the outer surface of the CuO nanowires. The CuO nanowire array has a length of 10–20 μm and a diameter of 100–150 nm. The zinc nanosheets are coated on the outer surface of the CuO nanowires by electron beam deposition.

2. The three-dimensional nanoarray zinc anode material as described in claim 1, characterized in that, The thickness of the zinc nanosheets is 90–180 nm.

3. A method for preparing a three-dimensional nanoarray zinc anode material according to any one of claims 1 to 2, characterized in that, Includes the following steps: (1) Copper foam cleaning: The copper foam was placed in 1M hydrochloric acid solution, acetone, and anhydrous ethanol in sequence, and then sonicated for 10-30 minutes in sequence. (2) Preparation of CF@Cu(OH)2 nanowires: A mixed solution of NaOH solution and ammonium persulfate solution is provided. The cleaned copper foam is reacted with the mixed solution. The reaction product is washed with deionized water and then vacuum dried at 50-70°C for 10-14 hours to obtain CF@Cu(OH)2 nanowires. (3) Preparation of CF@CuO nanowires: The CF@Cu(OH)2 nanowires were subjected to high-temperature annealing to obtain CF@CuO nanowires; (4) Preparation of CF@CuO@Zn three-dimensional nanoarray zinc anode material: The CF@CuO nanowires are placed on a coating tray and sent into the chamber of an electron beam coating instrument. After vacuuming, zinc is deposited. After the process is completed, the chamber is allowed to cool down to obtain the CF@CuO@Zn three-dimensional nanoarray zinc anode material.

4. The preparation method according to claim 3, characterized in that, In step (2), the concentration of NaOH solution is 4M and the concentration of ammonium persulfate solution is 0.2M; the reaction temperature in step (2) is room temperature and the reaction time is 5-10 min.

5. The preparation method according to claim 3, characterized in that, In step (3), the heating rate of high-temperature annealing is 60-90℃ / min, the high-temperature annealing temperature is 160-200℃, and the high-temperature annealing time is 0.5-1.5h.

6. The preparation method according to claim 3, characterized in that, In step (4), the vacuum level of the electron beam coating chamber is less than or equal to 1×10⁻⁶. -4 Pa; the reaction evaporation regulator is 8–9, the deposition rate is 0.3–0.6 Å / s, and the reaction time is 0.5–1 h.

7. The preparation method according to claim 3, characterized in that, In step (4), the CF@CuO@Zn three-dimensional nanoarray zinc anode material is sealed and stored.

8. The application of the three-dimensional nanoarray zinc anode material as described in any one of claims 1 to 2 and / or the three-dimensional nanoarray zinc anode material prepared by the preparation method as described in any one of claims 3 to 7 in energy conversion and storage.

Images