An inorganic-organic co-intercalated vanadium-based positive electrode material for zinc ion batteries and a preparation method thereof

Abstract

The application discloses an inorganic-organic intercalation vanadium-based positive electrode material for a zinc ion battery and a preparation method thereof, and relates to the technical field of zinc ion batteries. The preparation method comprises the following steps: mixing vanadium pentoxide, an H2O2 solution, a sodium salt and water to obtain a solution A; dissolving benzyltrimethylammonium chloride in water to obtain a solution B; and mixing the solution A and the solution B and performing a hydrothermal reaction to obtain the inorganic-organic intercalation vanadium-based positive electrode material for the zinc ion battery. The application has the advantages of mild reaction conditions, a simple preparation process, low equipment requirements and industrial feasibility. The inorganic-organic intercalation vanadium-based positive electrode material has a nanoflower-like micro-morphology, high discharge specific capacity and excellent electrochemical performances such as excellent cycle stability.

Description

Technical Field

[0001] This invention relates to the field of zinc-ion battery technology, and in particular to an inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries and its preparation method. Background Technology

[0002] Renewable energy sources such as wind and solar power are characterized by significant intermittency and instability, and their large-scale grid-connected application relies on efficient energy storage technologies. Against this backdrop, traditional lithium-ion batteries, which rely on flammable organic electrolytes, pose safety hazards. In contrast, aqueous zinc-ion batteries, with their inherent safety, low cost, high theoretical capacity (820 mAh / g), and low redox potential, have become important candidates for next-generation energy storage systems.

[0003] Currently, the development of aqueous zinc-ion batteries is still in its early stages. Cathode materials play a crucial role in the research of zinc storage mechanisms and the construction of high-performance batteries. Common cathode materials include manganese-based oxides, vanadium-based oxides, vanadium-based nitrides, Prussian blue and its analogues, metal / covalent organic framework compounds, layered MXenes, layered sulfides, and selenides. Among numerous cathode candidates, vanadium pentoxide (V₂O₅) exhibits a theoretical capacity as high as 589 mAh / g, based on the redox properties of vanadium's multiple valence states (V₅⁺ / V₄⁺ / V₃⁺) and its tunable tunnel structure. However, the inherent structural instability, significant electrostatic interactions, and slow reaction kinetics of V₂O₅ severely limit its zinc storage capacity and cycle life, making it difficult to meet the requirements of large-scale applications. Therefore, providing a structurally stable aqueous vanadium-based zinc-ion battery cathode material is an urgent problem to be solved. Summary of the Invention

[0004] The purpose of this invention is to provide an inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries and its preparation method, thereby solving the problems existing in the prior art. The preparation method of this invention is simple, and the resulting inorganic-organic co-intercalated vanadium-based cathode material exhibits a nano-flower-like microstructure. When applied to aqueous zinc-ion batteries, the inorganic-organic co-intercalated vanadium-based cathode material prepared by this invention demonstrates ultra-high discharge capacity and excellent cycle stability, particularly at low current densities. At a current density of 1 A / g, the highest discharge specific capacity reaches 240.5 mAh / g; at a current density of 5 A / g, the discharge specific capacity retention rate after 3000 cycles is 92.2%, and the initial discharge specific capacity reaches 150.0 mAh / g.

[0005] To achieve the above objectives, the present invention provides the following solution: One of the technical solutions of the present invention: a method for preparing an inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries, comprising the following steps: mixing vanadium pentoxide (V₂O₅), H₂O₂ solution, sodium salt and water to obtain solution A; and mixing benzyltrimethylammonium chloride (C₂O₅) with water to obtain solution A. 10 H 16 NCl (abbreviated as BTAC) is dissolved in water to obtain solution B; solution A and solution B are mixed and subjected to a hydrothermal reaction to obtain the inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries (i.e., inorganic cation and organic cation co-intercalated vanadium-based zinc-ion battery cathode material).

[0006] The preparation method of this invention involves mixing vanadium oxide (V₂O₅) with sodium salt and benzyltrimethylammonium chloride to synthesize an inorganic-organic co-intercalated vanadium-based cathode material via a one-step hydrothermal method. During the synthesis process, sodium cations (Na₂O₅, Na ... + ) and benzyltrimethylammonium cation (BTA) + The intercalation of Na into the interlayer space of vanadium oxide contributes to widening the interlayer spacing and stabilizing the layered structure. + Not only does it act as a rigid interlayer support to widen the interlayer spacing, but it also regulates the electronic environment by inducing vanadium valence state reconstruction, reducing the electron transport energy barrier, and significantly improving the electronic conductivity of the material; BTA + The benzyl ring provides spatial support, further stabilizing the integrity of the layered structure; its hydrophobic benzyl group can form an "interfacial barrier," essentially inhibiting water molecule insertion and promoting Zn... 2+ The process of desolvation is effectively inhibited, thereby comprehensively optimizing charge storage performance. The preparation method has mild reaction conditions, simple preparation process, and low equipment requirements.

[0007] Furthermore, the sodium salt includes sodium chloride (NaCl).

[0008] Furthermore, the concentration of the H2O2 solution is 30 vol%.

[0009] Furthermore, the molar ratio of vanadium pentoxide to sodium salt is 2:0.5~5, preferably 2:0.5~2.

[0010] Furthermore, the ratio of vanadium pentoxide to the H2O2 solution is 2 mmol: 2~5 mL.

[0011] Furthermore, the ratio of vanadium pentoxide to water in solution A is 1 mmol: 20~40 mL.

[0012] Furthermore, the molar ratio of vanadium pentoxide in solution A to benzyltrimethylammonium chloride in solution B is 2:0.5~5, preferably 2:0.5~2.

[0013] Furthermore, the ratio of benzyltrimethylammonium chloride to water in solution B is 1 mmol: 10~30 mL.

[0014] Furthermore, the hydrothermal reaction is carried out at a temperature of 100~180 ℃ for a time of 6~24 h.

[0015] Preferably, the hydrothermal reaction is carried out at a temperature of 100 °C for 12 h.

[0016] Further, the preparation steps of solution A include: dispersing vanadium pentoxide in water, stirring for 20-40 min, then adding H2O2 solution, continuing to stir for 20-40 min, then adding sodium salt, and stirring evenly to obtain solution A.

[0017] Furthermore, after the hydrothermal reaction is completed, the process also includes centrifugation or filtration, washing, and drying.

[0018] Preferably, the washing is specifically performed with deionized water or anhydrous ethanol.

[0019] Preferably, the drying temperature is 40~80 ℃ and the time is 8~24 h.

[0020] More preferably, the drying temperature is 60 °C and the time is 12 h. Excessively high drying temperatures will damage the structure of the cathode material, causing a significant reduction in its electrochemical performance.

[0021] The second technical solution of the present invention: an inorganic-organic co-intercalated vanadium-based cathode material prepared by the above-described method for preparing inorganic-organic co-intercalated vanadium-based cathode materials for zinc-ion batteries.

[0022] Furthermore, the inorganic-organic co-intercalated vanadium-based cathode material is specifically [Na 0.02 (C 10 H 16 N) 0.19 V2O5·0.8H2O.

[0023] Furthermore, the microstructure of the inorganic-organic co-intercalated vanadium-based cathode material is nanoflower-like.

[0024] The third technical solution of the present invention: the application of the above-mentioned inorganic-organic co-intercalated vanadium-based cathode material in the preparation of cathode electrode sheets or aqueous zinc-ion batteries.

[0025] The fourth technical solution of the present invention: a positive electrode sheet, the raw material of which includes the above-mentioned inorganic-organic co-intercalated vanadium-based positive electrode material.

[0026] The fifth technical solution of the present invention: an aqueous zinc-ion battery, the raw materials of which include the above-mentioned inorganic-organic co-intercalated vanadium-based cathode material.

[0027] Furthermore, the negative electrode of the aqueous zinc-ion battery is zinc foil, the electrolyte is zinc trifluoromethanesulfonate solution, and the separator is a glass fiber separator.

[0028] Furthermore, the concentration of zinc trifluoromethanesulfonate in the electrolyte is 3~6 mol / L.

[0029] Furthermore, the preparation steps of the positive electrode sheet of the aqueous zinc-ion battery include: uniformly mixing the inorganic-organic co-intercalated vanadium-based positive electrode material, conductive carbon black, polyvinylidene fluoride (PVDF) and N-methylpyrrolidone to form a slurry, coating it on titanium foil, and drying it to obtain the positive electrode sheet.

[0030] Preferably, the mass ratio of the inorganic-organic co-intercalated vanadium-based cathode material, conductive carbon black, and polyvinylidene fluoride is 7:2:1.

[0031] Preferably, the positive electrode material loading of the positive electrode sheet is 1.5~3 mg / cm³. 2 .

[0032] The present invention discloses the following technical effects: 1. The preparation method of the present invention involves mixing vanadium oxide with sodium chloride and benzyltrimethylammonium chloride, and the final inorganic-organic co-intercalated vanadium-based cathode material can be prepared by a simple one-step hydrothermal method; the reaction conditions of the present invention are mild, the preparation process is simple, and the equipment requirements are low; the cathode material obtained by the present invention has a nano-flower-like microstructure.

[0033] 2. The zinc-ion battery prepared using the cathode material of the present invention has an ultra-high discharge specific capacity and excellent cycle stability, and has good rate performance; the discharge specific capacity can reach up to 240.5 mAh / g at a current density of 1 A / g; at a current density of 5 A / g, the discharge specific capacity retention rate is 92.2% after 3000 cycles, and the initial discharge specific capacity reaches 150.0 mAh / g.

[0034] 3. Na in the synthesis process of this invention + With BTA + Intercalation into the interlayer space of vanadium oxides collectively widens the interlayer spacing and stabilizes the layered structure. Among them, Na... + Not only does it act as a rigid interlayer support to widen the interlayer spacing, but it also regulates the electronic environment by inducing vanadium valence state reconstruction, reducing the electron transport energy barrier, and significantly improving the electronic conductivity of the material; BTA +The benzyl ring provides spatial support, further stabilizing the integrity of the layered structure; its hydrophobic benzyl group can form an "interfacial barrier," essentially inhibiting water molecule insertion and promoting Zn... 2+ The desolvation process effectively suppresses vanadium dissolution, thereby comprehensively optimizing charge storage performance. As a result, the battery exhibits ultra-high capacity and excellent cycle stability, providing a valuable new approach for the design and development of inorganic-organic co-intercalated vanadium-based cathode materials for advanced aqueous zinc-ion batteries (AZIBs).

[0035] 4. The negative electrode raw materials used in the aqueous zinc-ion battery of this invention are abundant and inexpensive; the electrolyte zinc trifluoromethanesulfonate is inexpensive, safe and environmentally friendly. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 The image shows the XRD pattern of the inorganic-organic co-intercalated vanadium-based cathode material prepared in Example 1.

[0038] Figure 2 This is a SEM image of the inorganic-organic co-intercalated vanadium-based cathode material prepared in Example 2.

[0039] Figure 3 The image shows the elemental mapping of the inorganic-organic co-intercalated vanadium-based cathode material prepared in Example 1.

[0040] Figure 4 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in Example 1 at a constant current of 1 A / g.

[0041] Figure 5 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in Example 1 at a constant current of 5 A / g.

[0042] Figure 6 The graph shows the rate performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in Example 1.

[0043] Figure 7 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the organic intercalated vanadium-based cathode material prepared in Comparative Example 1 at a constant current of 1 A / g.

[0044] Figure 8 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the organic intercalated vanadium-based cathode material prepared in Comparative Example 1 at a constant current of 5 A / g.

[0045] Figure 9 The rate performance of an aqueous zinc-ion battery assembled using the organic intercalated vanadium-based cathode material prepared in Comparative Example 1 is shown.

[0046] Figure 10 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic intercalated vanadium-based cathode material prepared in Comparative Example 2 at a constant current of 1 A / g.

[0047] Figure 11 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic intercalated vanadium-based cathode material prepared in Comparative Example 2 at a constant current of 5 A / g.

[0048] Figure 12 The rate performance diagram shows the aqueous zinc-ion battery assembled using the inorganic intercalated vanadium-based cathode material prepared in Comparative Example 2.

[0049] Figure 13 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the vanadium-based cathode material prepared in Comparative Example 3 at a constant current of 1 A / g.

[0050] Figure 14 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the vanadium-based cathode material prepared in Comparative Example 3 at a constant current of 5 A / g.

[0051] Figure 15 The rate performance of an aqueous zinc-ion battery assembled using the vanadium-based cathode material prepared in Comparative Example 3 is shown in the figure.

[0052] Figure 16 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in Comparative Example 4 at a constant current of 5 A / g.

[0053] Figure 17 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in Comparative Example 5 at a constant current of 5 A / g. Detailed Implementation

[0054] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0055] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0056] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0057] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0058] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0059] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0060] Unless otherwise specified, the room temperature mentioned in the following examples and comparative examples refers to 20-30 ℃.

[0061] Unless otherwise specified, the experimental methods used in the following examples and comparative examples are conventional methods; and the reagents, materials and equipment used are commercially available unless otherwise specified.

[0062] Example 1 1. Inorganic-organic co-intercalated vanadium-based cathode material (i.e., Na) + BTA + The preparation of co-doped V₂O₅ follows these steps: Disperse 2 mmol V₂O₅ in 60 mL of deionized water and stir magnetically for 30 min. Then add 2 mL of 30 vol% H₂O₂ solution and stir for 30 min to form a black transparent solution. Add 1 mmol NaCl and stir until homogeneous to obtain solution A. Simultaneously, add 1 mmol C... 10 H 16 NCl was dissolved in 20 mL of deionized water to form a colorless and transparent solution B. Solution A and solution B were mixed and transferred to a 100 mL polytetrafluoroethylene-lined stainless steel autoclave. The autoclave was heated at 100 °C for 12 h. After the reaction was completed, the material was centrifuged, washed with deionized water, and vacuum dried at 60 °C for 12 h to obtain an inorganic-organic co-intercalated vanadium-based cathode material.

[0063] Figure 1 The X-ray diffraction (XRD) pattern of the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment shows that its structure (chemical formula) is [Na] after XRD analysis. 0.02 (C 10 H 16 N) 0.19 V2O5·0.8H2O.

[0064] Figure 2 The scanning electron microscope (SEM) image of the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment shows that the microstructure of the obtained cathode material is nanoflower-like, and the nanosheets are stacked in a disordered manner.

[0065] Figure 3 The mapping elemental analysis diagram of the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment shows that V, Na, N, C, and O elements are uniformly distributed.

[0066] 2. The preparation steps of a rechargeable aqueous zinc-ion battery are as follows: (1) Preparation of the positive electrode sheet: The inorganic-organic co-intercalated vanadium-based cathode material prepared above, conductive carbon black (acetylene black), polyvinylidene fluoride (PVDF), and N-methylpyrrolidone were mixed evenly to form a slurry (the mass ratio of cathode material, conductive carbon black, and PVDF was 7:2:1). This slurry was coated onto a titanium foil (the thickness of the titanium foil was 20 μm) and dried to obtain a cathode electrode sheet (the cathode material loading was 2 mg / cm³). 2 ).

[0067] (2) Preparation of negative electrode sheet: The negative electrode is a zinc foil with a thickness of 20 μm. The oxide layer is removed by sonication with acetone for 20 min, then rinsed with ethanol and dried to obtain the negative electrode sheet.

[0068] (3) Preparation of electrolyte: Weigh 1.09 g of zinc trifluoromethanesulfonate and dissolve it in 1 mL of deionized water to prepare an electrolyte (concentration of 3 mol / L).

[0069] (4) Battery fabrication: The electrode plates are placed in the battery case, and a Whatman glass fiber (GF / D) separator is placed between the positive and negative electrode plates. 70 μL of electrolyte is added, and then the battery is encapsulated to obtain a rechargeable aqueous zinc-ion battery (specifically a CR2032 coin cell).

[0070] 3. Battery performance test: The cycle performance of zinc-ion batteries was tested under a constant temperature environment of 25 ℃, with a current density of 1 A / g and a cutoff voltage of 0.2~1.6 V. Figure 4 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment under a constant current of 1 A / g. Calculated by the mass of the active material of the cathode, the initial discharge specific capacity is 240.5 mAh / g, which decreases to 210.7 mAh / g after 100 cycles, with a capacity retention rate of 87.6% during cycling. This indicates that the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment has a large specific capacity and a high capacity retention rate when applied to zinc-ion batteries.

[0071] Figure 5 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment under a constant current of 5 A / g (test temperature: 25 °C, cutoff voltage: 0.2~1.6 V). It can be seen that the initial discharge specific capacity is 150.0 mAh / g. After 2000 cycles, the capacity decays to 141.8 mAh / g, with a capacity retention rate of 94.5%. After 3000 cycles, the capacity decays to 138.33 mAh / g, with a capacity retention rate of 92.2%. The highest discharge specific capacity during cycling reaches 154.0 mAh / g. This indicates that the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment exhibits good cycle stability when applied to zinc-ion batteries.

[0072] Figure 6 To obtain the rate performance profile (test temperature 25 °C, cutoff voltage 0.2~1.6 V) of the aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment, the test was conducted after pre-activating the aqueous zinc-ion battery for five cycles at a current density of 0.1 A / g. Figure 6As shown, its initial discharge specific capacity is 308.6 mAh / g at a current density of 0.1 A / g, 245.4 mAh / g at 0.5 A / g, 227.0 mAh / g at 1 A / g, 189.3 mAh / g at 3 A / g, and 166.4 mAh / g at 5 A / g. When the current density increases from 0.1 A / g to 8 A / g, the specific capacity remains at 142.4 mAh / g. When the current density returns to 0.1 A / g, the specific capacity recovers to 262.3 mAh / g. This demonstrates that the inorganic-organic co-intercalated vanadium-based cathode material prepared in this embodiment exhibits excellent rate performance when applied to zinc-ion batteries.

[0073] Comparative Example 1 1. Organic intercalated vanadium-based cathode materials (i.e., BTA only) + Preparation of doped V₂O₅: The preparation steps are the same as in Example 1, except that NaCl is not added when preparing solution A.

[0074] 2. Preparation of rechargeable aqueous zinc-ion batteries: The preparation steps are the same as in Example 1, except that the organic intercalated vanadium-based cathode material prepared in this comparative example is used as the cathode material.

[0075] 3. Battery performance test: Figure 7 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the organic intercalated vanadium-based cathode material prepared in this comparative example under a constant current of 1 A / g (test temperature of 25 °C and cutoff voltage of 0.2~1.6 V). It can be seen that at a low current density of 1 A / g, the initial capacity is 195.7 mAh / g, and after 100 cycles, only 164.3 mAh / g remains, indicating poor performance.

[0076] Figure 8 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the organic intercalated vanadium-based cathode material prepared in this comparative example under a constant current of 5 A / g (test temperature of 25 °C, cutoff voltage of 0.2~1.6 V). It can be seen that at a current density of 5 A / g, the initial capacity is 109.1 mAh / g, and after 3000 cycles, only 84.7 mAh / g remains, with a capacity retention of 77.6%.

[0077] Figure 9To obtain the rate performance profile (test temperature 25 ℃, cutoff voltage 0.2~1.6 V) of the aqueous zinc-ion battery assembled using the organic intercalated vanadium-based cathode material prepared in this comparative example, the test was conducted after five cycles of pre-activation at a current density of 0.1 A / g. Figure 9 As shown, under the same test conditions as in Example 1, its initial discharge specific capacity is 272.9 mAh / g at a current density of 0.1 A / g, 218.0 mAh / g at a current density of 0.5 A / g, 199.9 mAh / g at a current density of 1 A / g, 165.8 mAh / g at a current density of 3 A / g, 145.7 mAh / g at a current density of 5 A / g, and 122.3 mAh / g at a current density of 8 A / g, indicating generally average rate performance.

[0078] A comparison of Comparative Example 1 and Example 1 shows that the stability, capacity, and rate performance of the organic intercalated vanadium-based cathode material in Comparative Example 1 are inferior to those in Example 1. This is because pure BTA... + Although doping increases the interlayer spacing and improves the cycle life and capacity of the battery to some extent, it cannot guide the valence state change of V in V2O5, resulting in overall performance that is not as good as inorganic-organic co-intercalated V2O5.

[0079] Comparative Example 2 1. Inorganic intercalated vanadium-based cathode materials (i.e., Na-only) + Preparation of doped V₂O₅: The preparation steps are the same as in Example 1, except that C is not added when preparing solution B. 10 H 16 NCl (i.e., using deionized water as solution B).

[0080] 2. Preparation of rechargeable aqueous zinc-ion batteries: The preparation steps are the same as in Example 1, except that the inorganic intercalated vanadium-based cathode material prepared in this comparative example is used as the cathode material.

[0081] 3. Battery performance test: Figure 10 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic intercalated vanadium-based cathode material prepared in this comparative example under a constant current of 1 A / g (test temperature of 25 ℃, cutoff voltage of 0.2~1.6 V). It can be seen that at a low current density of 1 A / g, the initial capacity is 178.4 mAh / g, and after 100 cycles, only 160.5 mAh / g remains, indicating poor performance.

[0082] Figure 11The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic intercalated vanadium-based cathode material prepared in this comparative example under a constant current of 5 A / g (test temperature of 25 °C, cutoff voltage of 0.2~1.6 V). It can be seen that at a current density of 5 A / g, the initial capacity is 105.2 mAh / g, and after 3000 cycles, only 66.3 mAh / g remains.

[0083] Figure 12 To obtain the rate performance profile (test temperature 25 ℃, cutoff voltage 0.2~1.6 V) of the aqueous zinc-ion battery assembled using the inorganic intercalated vanadium-based cathode material prepared in this comparative example, the test was conducted after pre-activating the aqueous zinc-ion battery for five cycles at a current density of 0.1 A / g. Figure 12 As shown, under the same test conditions as in Example 1, its initial discharge specific capacity is 288.6 mAh / g at a current density of 0.1 A / g, 235.4 mAh / g at a current density of 0.5 A / g, 213.9 mAh / g at a current density of 1 A / g, 169.8 mAh / g at a current density of 3 A / g, 116.1 mAh / g at a current density of 5 A / g, and 39.3 mAh / g at a current density of 8 A / g, indicating generally average rate performance.

[0084] By comparing Comparative Example 2 with Example 1, it can be seen that the stability, capacity, and rate performance of the inorganic intercalated vanadium-based cathode material in Comparative Example 2 are inferior to those in Example 1. This is because pure Na... + While doping improves the capacity of V2O5 at low current densities and stabilizes the cycle performance of the battery to some extent, it cannot expand the ion transport channels of V2O5, resulting in overall performance that is inferior to inorganic-organic co-intercalated V2O5.

[0085] Comparative Example 3 1. Preparation of vanadium-based cathode materials (VOH for short): The preparation steps are the same as in Example 1, except that NaCl is not added when preparing solution A, and C is not added when preparing solution B. 10 H 16 NCl.

[0086] 2. Preparation of rechargeable aqueous zinc-ion batteries: The preparation steps are the same as in Example 1, except that the vanadium-based cathode material prepared in this comparative example is used as the cathode material.

[0087] 3. Battery performance test: Figure 13The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the vanadium-based cathode material prepared in this comparative example under a constant current of 1 A / g (test temperature of 25 °C and cutoff voltage of 0.2~1.6 V). It can be seen that at a low current density of 1 A / g, the initial capacity is 145.6 mAh / g, and after 100 cycles, only 126.8 mAh / g remains, indicating poor performance.

[0088] Figure 14 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the vanadium-based cathode material prepared in this comparative example under a constant current of 5 A / g (test temperature of 25 °C and cutoff voltage of 0.2~1.6 V). It can be seen that at a current density of 5 A / g, the initial capacity is 70.9 mAh / g, and after 1500 cycles, only 40 mAh / g of capacity remains.

[0089] Figure 15 To obtain the rate performance profile (test temperature 25 ℃, cutoff voltage 0.2~1.6 V) of the aqueous zinc-ion battery assembled using the vanadium-based cathode material prepared in this comparative example, the test was conducted after five cycles of pre-activation at a current density of 0.1 A / g. Figure 15 As shown, under the same test conditions as in Example 1, its initial discharge specific capacity is 218.7 mAh / g at a current density of 0.1 A / g, 186.6 mAh / g at a current density of 0.5 A / g, 171.4 mAh / g at a current density of 1 A / g, 124.9 mAh / g at a current density of 3 A / g, 67.5 mAh / g at a current density of 5 A / g, and 13.9 mAh / g at a current density of 8 A / g, indicating generally average rate performance.

[0090] A comparison of Comparative Example 3 and Example 1 shows that the stability, capacity, and rate performance of the vanadium-based cathode material in Comparative Example 3 are inferior to those in Example 1. This is because the undoped VOH layer structure is unstable, has poor conductivity, and is prone to ion transport channel collapse, all of which limit the battery's cycle count and capacity, resulting in overall performance inferior to inorganic-organic co-intercalated V₂O₅. Example 1, by adding NaCl and C… 10 H 16 NCl, Na + With BTA + Intercalation into the interlayer space of vanadium oxides contributes to widening the interlayer spacing and stabilizing the layered structure. Among these, Na... + Not only does it act as a rigid interlayer support to widen the interlayer spacing, but it also regulates the electronic environment by inducing vanadium valence state reconstruction, reducing the electron transport energy barrier, and significantly improving the electronic conductivity of the material; BTA+ The benzyl ring provides spatial support, further stabilizing the integrity of the layered structure; its hydrophobic benzyl group can form an "interfacial barrier," essentially inhibiting water molecule insertion and promoting Zn... 2+ The desolvation process effectively suppresses vanadium dissolution, thereby comprehensively optimizing charge storage performance, resulting in ultra-high capacity and excellent cycle stability of the battery.

[0091] Comparative Example 4 1. Inorganic-organic co-intercalated vanadium-based cathode material (K + BTA + Preparation of co-doped V₂O₅: The preparation steps are the same as in Example 1, except that when preparing solution A, the equimolar amount of NaCl is replaced with KCl.

[0092] 2. Preparation of rechargeable aqueous zinc-ion batteries: The preparation steps are the same as in Example 1, except that the inorganic-organic co-intercalated vanadium-based cathode material prepared in this comparative example is used as the cathode material.

[0093] 3. Battery performance test: Figure 16 The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in this comparative example under a constant current of 5 A / g (test temperature of 25 °C, cutoff voltage of 0.2~1.6 V). It can be seen that at a current density of 5 A / g, the initial capacity is 101.3 mAh / g, and after 3000 cycles, only 82.5 mAh / g remains.

[0094] Comparative Example 5 1. Inorganic-organic co-intercalated vanadium-based cathode material (Mg 2+ BTA + Preparation of co-doped V₂O₅: The preparation steps are the same as in Example 1, except that when preparing solution A, the equimolar amount of NaCl is replaced with MgCl2.

[0095] 2. Preparation of rechargeable aqueous zinc-ion batteries: The preparation steps are the same as in Example 1, except that the inorganic-organic co-intercalated vanadium-based cathode material prepared in this comparative example is used as the cathode material.

[0096] 3. Battery performance test: Figure 17The graph shows the cycling performance of an aqueous zinc-ion battery assembled using the inorganic-organic co-intercalated vanadium-based cathode material prepared in this comparative example under a constant current of 5 A / g (test temperature of 25 °C, cutoff voltage of 0.2~1.6 V). It can be seen that at a current density of 5 A / g, the initial capacity is 153.1 mAh / g, and after 3000 cycles, only 85.2 mAh / g remains.

[0097] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing an inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries, characterized in that, Includes the following steps: Vanadium pentoxide, H2O2 solution, sodium salt and water are mixed to obtain solution A; benzyltrimethylammonium chloride is dissolved in water to obtain solution B; solution A and solution B are mixed and subjected to a hydrothermal reaction to obtain the inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries.

2. The method for preparing the inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries as described in claim 1, characterized in that, The sodium salt includes sodium chloride.

3. The method for preparing the inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries as described in claim 1, characterized in that, The concentration of the H2O2 solution is 30 vol.

4. The method for preparing the inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries as described in claim 1, characterized in that, The molar ratio of vanadium pentoxide to sodium salt is 2:0.5~5; And / or, the ratio of vanadium pentoxide to the H2O2 solution is 2 mmol: 2~5 mL.

5. The method for preparing the inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries as described in claim 1, characterized in that, The molar ratio of vanadium pentoxide in solution A to benzyltrimethylammonium chloride in solution B is 2:0.5~5.

6. The method for preparing the inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries as described in claim 1, characterized in that, The hydrothermal reaction is carried out at a temperature of 100~180 ℃ for a time of 6~24 h.

7. An inorganic-organic co-intercalated vanadium-based cathode material prepared by the method for preparing an inorganic-organic co-intercalated vanadium-based cathode material for zinc-ion batteries as described in any one of claims 1-6.

8. The application of the inorganic-organic co-intercalated vanadium-based cathode material as described in claim 7 in the preparation of cathode electrode sheets or aqueous zinc-ion batteries.

9. A positive electrode sheet, characterized in that, The raw material for the positive electrode sheet includes the inorganic-organic co-intercalated vanadium-based positive electrode material as described in claim 7.

10. An aqueous zinc-ion battery, characterized in that, The raw materials for the aqueous zinc-ion battery include the inorganic-organic co-intercalated vanadium-based cathode material as described in claim 7.

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