阅读说明：本技术 水系锌离子电池钒基正极材料及其制备方法与应用 (Vanadium-based positive electrode material of water-based zinc ion battery and preparation method and application thereof ) 是由 程红伟 鲁雄刚 王娜 孙强超 吕凡 于 2020-04-26 设计创作，主要内容包括：本发明公开了一种水系锌离子电池钒基正极材料,具有以下化学组成：M<Sub>x</Sub>V<Sub>2</Sub>O<Sub>5</Sub>·nH<Sub>2</Sub>O,所述M为Mg或Sn；0＜x≤2；0＜n≤2。其制备方法包括如下步骤：将五氧化二钒溶于去离子水,在搅拌后滴加酸性溶液,水浴搅拌待反应完全,将M盐溶于去离子水,完全溶解后滴入上述溶液,完全反应后进行水热反应。获得的正极材料装配成纽扣电池后进行电化学性能测试,测试时电流密度范围为0.1～10A g<Sup>-1</Sup>,电压范围为0.1～1.8V。该制备方法简单便捷,对实验条件要求较低。合成材料的微观形貌为纳米带状,具有更大的层间距,使层状结构更稳定,更有利于锌离子的脱嵌,装配得到的锌离子电池表现出优异的循环稳定性和倍率性能。(The invention discloses a vanadium-based cathode material of a water-based zinc ion battery, which comprises the following chemical compositions: m x V 2 O 5 ·nH 2 O, wherein M is Mg or Sn; x is more than 0 and less than or equal to 2; n is more than 0 and less than or equal to 2. The preparation method comprises the following steps: dissolving vanadium pentoxide in deionized water, dropwise adding an acid solution after stirring, stirring in a water bath until the reaction is complete, dissolving M salt in deionized water, dropwise adding the solution after complete dissolution, and carrying out hydrothermal reaction after complete reaction. The obtained positive electrode material is assembled into a button cell and then is subjected to electrochemical performance test, and the current density range during the test is 0.1-10A g ‑1 The voltage range is 0.1-1.8V. The preparation method is simple and convenient, and has low requirements on experimental conditions. The micro-appearance of the synthetic material is nano-belt-shaped, and the synthetic material has larger interlayer spacing, so that the laminated structure is formedThe method is more stable and more beneficial to the de-intercalation of zinc ions, and the zinc ion battery obtained by assembly shows excellent cycle stability and rate performance.)

1. The vanadium-based cathode material of the water-based zinc ion battery is characterized by comprising the following chemical compositions: m_xV₂O₅·nH₂O, wherein M is Mg or Sn; x is more than 0 and less than or equal to 2; n is more than 0 and less than or equal to 2.

2. The preparation method of the vanadium-based cathode material of the water-based zinc-ion battery according to claim 1, which is characterized by comprising the following steps:

a. putting 0.1-1 g of vanadium oxide into a beaker, adding 20-40 mL of deionized water, and stirring in a water bath at 30-50 ℃ for 20-40 min to form an orange solution, namely a solution A;

b. dropping 1-8 ml of acid solution into the solution A prepared in the step a and stirred in a water bath, and continuously stirring for 40-80 min under the water bath condition of the step (1) to form a dark brown uniform solution, namely a solution B;

c. putting 0.1-1 g of M salt into a beaker, adding 8-12 ml of deionized water, and stirring until the M salt is completely dissolved to form a colorless transparent solution called as a solution C, wherein M is Mg or Sn;

d. dropping the solution C prepared in the step C into the solution B prepared in the step B in water bath stirring, continuously stirring for 30-60 min, and then performing ultrasonic vibration for 1-3 h to ensure that the solution C and the solution B are mixed and then fully react to form a uniform bubble-free solution, namely a solution D;

e. pouring the solution D prepared in the step D into a reaction kettle, placing the reaction kettle in an oven, heating the reaction kettle at 160-220 ℃ for 36-72 hours to react, standing the reaction kettle at room temperature for 12-48 hours, and alternately washing the reaction product with ethanol and deionized water for 3-4 times; and then heating the zinc-ion battery for 10-15 hours at the set temperature of 40 ℃ in a vacuum drying oven, raising the temperature to 80 ℃, and heating for 10-15 hours to obtain a dark green powdery product, thereby obtaining the vanadium-based positive electrode material of the zinc-ion battery.

3. The method for producing a vanadium-based positive electrode material for an aqueous zinc-ion battery according to claim 2, characterized in that: in the step a, the vanadium oxide is any one of vanadium trioxide, vanadium pentoxide and vanadium dioxide.

4. The method for producing a vanadium-based positive electrode material for an aqueous zinc-ion battery according to claim 2, characterized in that: in the step b, the acidic solution is any one of hydrochloric acid, hydrogen peroxide and glacial acetic acid.

5. The method for producing a vanadium-based positive electrode material for an aqueous zinc-ion battery according to claim 2, characterized in that: in the step c, the magnesium salt is any one of magnesium acetate, magnesium chloride and magnesium nitrate; the tin salt is any one of stannic chloride, stannous oxalate and stannous chloride.

6. The application of the vanadium-based cathode material of the water-based zinc-ion battery according to claim 1, wherein the vanadium-based cathode material of the water-based zinc-ion battery is used as a cathode material to prepare the water-based zinc-ion battery.

7. The use of the aqueous zinc-ion battery vanadium-based positive electrode material according to claim 6, characterized in that: the water-system zinc ion battery vanadium-based positive electrode material, the acetylene black and the polytetrafluoroethylene are used as raw material components, and the mass ratio of the water-system zinc ion battery vanadium-based positive electrode material to the acetylene black to the polytetrafluoroethylene is (7-8): (1-2): 1, mixing the raw material components, grinding the mixture in a mortar for 1-3 hours, pressing the mixture into a film, and drying the film at 70-100 ℃ for 10-14 hours under a vacuum condition to obtain the positive plate of the water-based zinc ion battery.

8. The use of the aqueous zinc-ion battery vanadium-based positive electrode material according to claim 7, characterized in that: the aqueous zinc ion battery positive electrodeThe loading amount of the active substance of the tablet is 5-7 mg/cm²。

Technical Field

The invention relates to a preparation method and application of a zinc ion secondary battery anode material, in particular to a preparation method and application of a water system zinc ion secondary battery anode material, which is applied to the technical field of zinc ion batteries.

Background

The energy is the foundation of the existence and continuous development of the human society, and the acquisition and storage of the energy play an important role in the aspects of reasonably utilizing natural resources, developing low-carbon economy, promoting the sustainable development of the human society and the like. In the past decades, with the continuous consumption of fossil energy such as petroleum and coal, novel clean energy technologies such as solar energy, tidal energy and wind energy gradually get attention of society. Although clean energy has the advantages of no pollution, environmental friendliness, etc., it is also limited by periodicity and volatility, and it is difficult to achieve stable energy supply. The energy is stored by an energy storage system, which is an effective solution.

Lithium ion batteries have been the research focus in recent years, and have achieved great success in the field of portable electronics, but the development of lithium ion batteries is greatly limited due to the limited lithium resources, high cost and safety issues of organic electrolytes. However, the aqueous zinc ion battery has 820mA hg compared to the lithium ion battery^-1The theoretical capacity of the catalyst, lower oxidation-reduction potential and low cost. In addition, the aqueous zinc ion battery changes the electrolyte from an organic matter to an aqueous solution, so that the safety is higher, and meanwhile, the ionic conductivity of the aqueous electrolyte is higher by several orders of magnitude than that of the organic electrolyte, so that the aqueous zinc ion battery has higher rate performance. Currently, most studied cathode materials of water-based zinc ion batteries include manganese oxide, prussian blue analogues, vanadium oxide and the like, wherein the former two cathode materials have poor rate performance, low cycle stability or limited capacity. The vanadium oxide can make Zn when used as anode material because of larger interlayer spacing²⁺The vanadium pentoxide layered structure can be rapidly and freely embedded and removed, and the good and stable electrochemical performance is shown, thereby attracting more and more researchers to pay attention.

Recently, the metal has been usedMethods for improving the structural stability and cycling performance of vanadium oxides by intercalation of cations into the vanadium pentoxide layers, e.g., Nazar et al [ Nature energy.2016,16119, DOI:10.1038/NENERGY.2016.119 ] have studied Zn_0.25V₂O₅·nH₂The O is used as the positive electrode material of the zinc ion battery, has excellent performance, and has the capacity of 220mA h g at the current density of 15 DEG C^-1After 1000 cycles, the capacity retention rate reaches 80 percent, and the volume energy density is 450Wh L^-1(ii) a Mai et al [ Nano Lett.2018,18,1758-₂V₆O₁₆·1.63H₂O as a positive electrode material for zinc ion batteries is 1A g^-1The capacity under the current density is 213mAh g^-1The capacity retention rate after 500 cycles is 76%; qian et al [ Nano Lett.2020, https:// dx.doi.org/10.1021/acs. nanolett.0c00732 ] studied Ba_1.2V₆O₁₆·3H₂O as a positive electrode material for aqueous zinc ion batteries is 0.5A g^-1The capacity under the current density is 190.8mAh g^-1And the capacity retention rate after 200 cycles is 75.9%. However, the existing vanadium-based materials which can be used for water-based zinc ion batteries cannot completely meet the requirements, and the development of new cathode materials is still the key for improving the performance of the water-based zinc ion batteries, so that the future practical application of the zinc ion batteries is deeply influenced, and the demand for solving the technical problem is urgently needed.

Disclosure of Invention

In order to solve the problems of the prior art, the invention aims to overcome the defects of the prior art and provide a water-system zinc ion battery vanadium-based positive electrode material, a method and application thereof; the obtained cathode material has higher specific discharge capacity and better cycling stability when being applied to a water system zinc ion battery.

In order to achieve the purpose of the invention, the invention adopts the following technical scheme:

a vanadium-based cathode material of a water-based zinc ion battery has the following chemical composition: m_xV₂O₅·nH₂O, the M is Mg orSn；0＜x≤2；0＜n≤2。

The invention discloses a preparation method of a water-based zinc ion battery vanadium-based cathode material, which is characterized by comprising the following steps of:

a. putting 0.1-1 g of vanadium oxide into a beaker, adding 20-40 mL of deionized water, and stirring in a water bath at 30-50 ℃ for 20-40 min to form an orange solution, namely a solution A;

b. dropping 1-8 ml of acid solution into the solution A prepared in the step a and stirred in a water bath, and continuously stirring for 40-80 min under the water bath condition of the step (1) to form a dark brown uniform solution, namely a solution B;

c. putting 0.1-1 g of M salt into a beaker, adding 8-12 ml of deionized water, and stirring until the M salt is completely dissolved to form a colorless transparent solution called as a solution C, wherein M is Mg or Sn;

d. dropping the solution C prepared in the step C into the solution B prepared in the step B in water bath stirring, continuously stirring for 30-60 min, and then performing ultrasonic vibration for 1-3 h to ensure that the solution C and the solution B are mixed and then fully react to form a uniform bubble-free solution, namely a solution D;

e. pouring the solution D prepared in the step D into a reaction kettle, placing the reaction kettle in an oven, heating the reaction kettle at 160-220 ℃ for 36-72 hours to react, standing the reaction kettle at room temperature for 12-48 hours, and alternately washing the reaction product with ethanol and deionized water for 3-4 times; and then heating the zinc-ion battery for 10-15 hours at the set temperature of 40 ℃ in a vacuum drying oven, raising the temperature to 80 ℃, and heating for 10-15 hours to obtain a dark green powdery product, thereby obtaining the vanadium-based positive electrode material of the zinc-ion battery.

As a preferable technical solution of the present invention, in the step a, the vanadium oxide is any one of vanadium trioxide, vanadium pentoxide, and vanadium dioxide.

In a preferred embodiment of the present invention, in the step b, the acidic solution is any one of hydrochloric acid, hydrogen peroxide and glacial acetic acid.

In a preferred embodiment of the present invention, in the step c, the magnesium salt is any one of magnesium acetate, magnesium chloride and magnesium nitrate; the tin salt is any one of stannic chloride, stannous oxalate and stannous chloride.

The invention relates to an application of a water-system zinc-ion battery vanadium-based cathode material, which is used as a cathode material to prepare a water-system zinc-ion battery.

According to a preferable technical scheme of the invention, the water-based zinc ion battery vanadium-based positive electrode material, the acetylene black and the polytetrafluoroethylene are used as raw material components, and the mass ratio of the water-based zinc ion battery vanadium-based positive electrode material to the acetylene black to the polytetrafluoroethylene is (7-8): (1-2): 1, mixing the raw material components, grinding the mixture in a mortar for 1-3 hours, pressing the mixture into a film, and drying the film at 70-100 ℃ for 10-14 hours under a vacuum condition to obtain the positive plate of the water-based zinc ion battery.

According to a preferred embodiment of the present invention, the loading amount of the active material in the positive electrode sheet of the aqueous zinc-ion battery is 5 to 7mg/cm²。

Compared with the prior art, the invention has the following prominent substantive characteristics and remarkable advantages:

1. the vanadium-based positive electrode material of the water-based zinc ion battery has a vanadium-based material (M ═ Mg, Sn) doped with M (M ═ Mg, Sn) cations and with crystal water_xV₂O₅·nH₂O) is a nano-belt structure, M cations and crystal water are embedded between layers, the interlayer spacing of the crystal structure is enlarged, and Zn is facilitated²⁺The de-intercalation of the material plays a role of a pillar, the structural stability is improved, and the material has better circulation stability and higher specific capacity;

2. the method has simple process, easy realization and very obvious economic benefit.

Drawings

FIG. 1 shows Mg as the positive electrode material of zinc-ion battery prepared by the method of example 1_xV₂O₅·nH₂X-ray diffraction (XRD) pattern of O.

FIG. 2 shows Mg as the positive electrode material of zinc-ion battery prepared by the method of example 1_xV₂O₅·nH₂Scanning Electron Microscope (SEM) image of O.

FIG. 3 shows Mg as the positive electrode material of zinc-ion battery prepared by the method of example 1_xV₂O₅·nH₂O at 1A g^-1Long cycle performance plot at current density.

FIG. 4 shows Mg as the positive electrode material of zinc-ion battery prepared by the method of example 1_xV₂O₅·nH₂Graph of rate capability of O.

FIG. 5 shows Mg as the positive electrode material of zinc-ion battery prepared by the method of example 1_xV₂O₅·nH₂O at 5A g^-1Long cycle performance plot at current density.

FIG. 6 shows the positive electrode material Mg of zinc ion battery prepared by the method of embodiment 4 of the invention_xV₂O₅·nH₂X-ray diffraction (XRD) pattern of O.

FIG. 7 shows Mg as the positive electrode material of zinc-ion battery prepared by the method of example 4_xV₂O₅·nH₂O at 1A g^-1Long cycle performance plot at current density.

FIG. 8 shows positive electrode material V for zinc-ion battery prepared in comparative example 1₂O₅·nH₂O at 1A g^-1Long cycle performance plot at current density.

FIG. 9 shows Mg as a positive electrode material for a zinc-ion battery prepared in comparative example 2_xV₂O₅At 1A g^-1Long cycle performance plot at current density.

Detailed Description

The above-described scheme is further illustrated below with reference to specific embodiments, which are detailed below: