阅读说明：本技术 一种v2o3纳米颗粒的制备方法 (V-shaped groove2O3Method for preparing nanoparticles ) 是由 黄剑锋 王羽偲嘉 李嘉胤 曹丽云 胡云飞 罗晓敏 王芳敏 于 2021-01-18 设计创作，主要内容包括：本发明公开了一种V-2O-3纳米颗粒的制备方法,首先将钒源与硫源溶于无水乙醇中,室温下搅拌均匀后进行溶剂热反应,得到硫化钒前驱体,将产物洗涤干净并冷冻干燥；然后将硫化钒前驱体在管式炉惰性气氛下煅烧,研磨得V-2O-3纳米颗粒。本发明通过溶剂热—煅烧两步法得到,将钒源与硫源充分均匀混合进行溶剂热反应,然后将硫化钒前驱体在管式炉中煅烧得到最终产品。本发明提供的V-2O-3结构为100nm左右的纳米颗粒,结构均匀。本发明合成V-2O-3方法简单,成本低,反应温度低,降低能耗；产品粒径小,纯度高。(The invention discloses a V 2 O 3 Firstly, dissolving a vanadium source and a sulfur source in absolute ethyl alcohol, uniformly stirring at room temperature, carrying out a solvothermal reaction to obtain a vanadium sulfide precursor, washing the product, and freeze-drying; then calcining the vanadium sulfide precursor in a tube furnace under inert atmosphere, and grinding to obtain V 2 O 3 And (3) nanoparticles. The vanadium sulfide is obtained by a solvothermal-calcination two-step method, a vanadium source and a sulfur source are fully and uniformly mixed for solvothermal reaction, and then a vanadium sulfide precursor is calcined in a tubular furnace to obtain a final product. V provided by the invention 2 O 3 The structure is about 100nm of nano particles and is uniform. The invention is concerned withTo form V 2 O 3 The method is simple, the cost is low, the reaction temperature is low, and the energy consumption is reduced; the product has small particle size and high purity.)

1. V-shaped groove₂O₃A method for preparing nanoparticles, characterized by comprising the steps of:

the method comprises the following steps: firstly, mixing a vanadium source and a sulfur source according to the ratio of V: s is 1: (6-8.13) dissolving the mixture in absolute ethyl alcohol according to the molar ratio, uniformly stirring at room temperature, carrying out solvent thermal reaction to obtain a vanadium sulfide precursor, washing the product, and freeze-drying;

step two: calcining the vanadium sulfide precursor in a tube furnace under inert atmosphere, and grinding to obtain V₂O₃And (3) nanoparticles.

2. V according to claim 1₂O₃The preparation method of the nano-particles is characterized by comprising the following steps: the vanadium source is one or a mixture of sodium metavanadate, vanadium chloride and vanadium acetylacetonate.

3. V according to claim 1₂O₃The preparation method of the nano-particles is characterized by comprising the following steps: the sulfur source is one or a mixture of thioacetamide and thiourea.

4. V according to claim 1₂O₃The preparation method of the nano-particles is characterized by comprising the following steps: the stirring time is 0.5-4 h.

5. V according to claim 1₂O₃The preparation method of the nano-particles is characterized by comprising the following steps: the solvothermal reaction temperature is 180-200 ℃, and the reaction time is 4-16 h.

6. V according to claim 1₂O₃The preparation method of the nano-particles is characterized by comprising the following steps: the inert atmosphere of the tubular furnace is argon or argon-hydrogen mixed gas.

7. V according to claim 1₂O₃The preparation method of the nano-particles is characterized by comprising the following steps: the calcination is to heat the mixture from room temperature to 500-700 ℃ at a heating rate of 2-10 ℃/min, and keep the temperature for 2-4 hours.

Technical Field

The invention belongs to the field of battery electrode materials, and particularly relates to a V₂O₃A method for preparing nanoparticles.

Background

With the real arrival of smart grid, renewable energy large-scale energy storage system and electric vehicle era, the development of advanced energy storage system is very important. Lithium Ion Batteries (LIBs) are preferred for their excellent energy and power density, good safety and long life (Li M, Lu J, Chen Z, et al.30 layers of Lithium-Ion batteries J]Advanced Materials,2018: 1800561.). It is well known that the electrode material plays a decisive role in the performance of LIBs. Vanadium-based oxides, a plentiful and inexpensive transition metal oxide on earth, are receiving wide attention for their excellent energy density and specific capacity. V₂O₃Because of its high theoretical specific capacity and low price, it is one of the candidates for excellent negative electrode material of lithium ion battery. However, at present V₂O₃The synthesis method is complex, and the high-valence vanadium compound is reduced mainly by a method of adding a reducing agent, but the method has the defects of high required reduction temperature, high energy consumption, low product purity, unsafety and the like.

Disclosure of Invention

The invention aims to provide V with simple preparation process₂O₃Method for preparing nanoparticles, prepared V₂O₃The nanoparticles have high purity and high crystallinity.

In order to achieve the purpose, the preparation method adopted by the invention comprises the following steps:

the method comprises the following steps: firstly, mixing a vanadium source and a sulfur source according to the ratio of V: s is 1: (6-8.13) dissolving the mixture in absolute ethyl alcohol according to the molar ratio, uniformly stirring at room temperature, carrying out solvent thermal reaction to obtain a vanadium sulfide precursor, washing the product, and freeze-drying;

step two: calcining the vanadium sulfide precursor in a tube furnace under inert atmosphere, and grinding to obtain V₂O₃And (3) nanoparticles.

The vanadium source is one or a mixture of sodium metavanadate, vanadium chloride and vanadium acetylacetonate.

The sulfur source is one or a mixture of thioacetamide and thiourea.

The stirring time is 0.5-4 h.

The solvothermal reaction temperature is 180-200 ℃, and the reaction time is 4-16 h.

The inert atmosphere of the tubular furnace is argon or argon-hydrogen mixed gas.

The calcination is to heat the mixture from room temperature to 500-700 ℃ at a heating rate of 2-10 ℃/min, and keep the temperature for 2-4 hours.

Compared with the prior art, the invention has the following beneficial effects:

(1) the invention adopts a solvothermal-calcination two-step method, overcomes the defects of high energy consumption, low purity and the like of the existing production process, has the advantages of simple process, low energy consumption, high yield, low equipment requirement, mild conditions and the like, is suitable for large-scale production, and reduces the production cost.

(2) V prepared by the invention₂O₃The electrode material has high purity and crystallinity. The particles with the size of about 100nm have uniform structure and are beneficial to improving the electrochemical performance. Has wide application prospect in the application process of the lithium ion battery cathode material.

Drawings

FIG. 1 is V prepared in example 2₂O₃The XRD diffractogram of (1), wherein the abscissa is the angle 2 θ and the ordinate is the intensity.

FIG. 2 is V prepared in example 2₂O₃SEM image of (d).

FIG. 3 is V prepared in example 3₂O₃The XRD diffractogram of (1), wherein the abscissa is the angle 2 θ and the ordinate is the intensity.

FIG. 4 is V prepared in example 3₂O₃SEM image of (d).

FIG. 5 shows V prepared in examples 2 and 3₂O₃In which the abscissa is the number of cycles and the ordinate is the capacity (mAh/g).

Detailed Description

Example 1:

the method comprises the following steps: firstly, mixing sodium metavanadate and thioacetamide according to the ratio of V: s is 1: dissolving the mixture in absolute ethyl alcohol according to the molar ratio of 6, stirring the mixture for 0.5 hour at room temperature, uniformly stirring the mixture, carrying out solvothermal reaction for 4 hours at 180 ℃ to obtain a vanadium sulfide precursor, washing the product clean, and freeze-drying the product;

step two: heating the vanadium sulfide precursor to 500 ℃ from room temperature at the heating rate of 2 ℃/min in the argon atmosphere in a tube furnace, calcining for 2 hours, and grinding to obtain V₂O₃And (3) nanoparticles.

Example 2:

the method comprises the following steps: firstly, mixing sodium metavanadate and thiourea according to the ratio of V: s is 1: dissolving the mixture in absolute ethyl alcohol according to the molar ratio of 6, stirring the mixture for 2 hours at room temperature, carrying out solvothermal reaction for 10 hours at 180 ℃ to obtain a vanadium sulfide precursor, washing the product, and freeze-drying the product;

step two: heating the vanadium sulfide precursor to 500 ℃ from room temperature at the heating rate of 2 ℃/min in the argon-hydrogen mixed gas atmosphere in a tube furnace, calcining for 2 hours, and grinding to obtain V₂O₃And (3) nanoparticles.

As can be seen from FIG. 1, the diffraction peaks all point to JCPDS84-0317 PDF card, and the synthesis of pure-phase V is proved₂O₃。

From FIG. 2, V can be seen₂O₃The nano particles are uniformly dispersed and are about 100nm particles.

Example 3:

the method comprises the following steps: firstly, mixing vanadium chloride and cysteine according to the ratio of V: s is 1: dissolving the mixture in absolute ethyl alcohol according to the molar ratio of 6, stirring the mixture for 2 hours at room temperature, carrying out solvothermal reaction for 16 hours at 180 ℃ to obtain a vanadium sulfide precursor, washing the product, and freeze-drying the product;

step two: heating the vanadium sulfide precursor to 700 ℃ from room temperature at a heating rate of 4 ℃/min in an argon-hydrogen mixed gas atmosphere in a tube furnace, calcining for 2 hours, and grinding to obtain V₂O₃And (3) nanoparticles.

From FIG. 3, it can be seen that the diffraction peaks all point to JCPDS71-0342 PDF card, demonstrating that pure phase V is synthesized₂O₃。

From FIG. 4, V can be seen₂O₃The nano particles are uniformly dispersed and are about 100nm particles.

FIG. 5 shows V of examples 2 and 3₂O₃And the nano particles are used as an electrochemical performance diagram of the lithium ion battery cathode material. As can be seen from the figure, both samples have good rate performance. Of these, example 2 possessed a higher capacity, exhibiting a capacity of 245mAh/g at a current density of 0.1A/g.

Example 4:

the method comprises the following steps: firstly, mixing vanadium acetylacetonate and thioacetamide according to the ratio of V: s is 1: dissolving the mixture in absolute ethyl alcohol according to the molar ratio of 6.5, stirring the mixture for 4 hours at room temperature, carrying out solvothermal reaction for 12 hours at 200 ℃ to obtain a vanadium sulfide precursor, washing the product clean, and freeze-drying the product;

step two: heating the vanadium sulfide precursor to 550 ℃ from room temperature at the heating rate of 6 ℃/min in the argon-hydrogen mixed gas atmosphere in a tube furnace, calcining for 3.5 hours, and grinding to obtain V₂O₃And (3) nanoparticles.

Example 5:

the method comprises the following steps: firstly, mixing sodium metavanadate, thioacetamide and thiourea according to the ratio of V: s is 1: dissolving the mixture in absolute ethyl alcohol according to the molar ratio of 7, stirring the mixture for 1 hour at room temperature, carrying out solvothermal reaction for 6 hours at 195 ℃ to obtain a vanadium sulfide precursor, washing the product, and freeze-drying the product;

step two: heating the vanadium sulfide precursor to 650 ℃ from room temperature at the heating rate of 8 ℃/min in the argon atmosphere in a tube furnace, calcining for 2.5 hours, and grinding to obtain V₂O₃And (3) nanoparticles.

Example 6:

the method comprises the following steps: firstly, mixing a mixture of sodium metavanadate and vanadium chloride with a mixture of thioacetamide, thiourea and cysteine according to the ratio of V: s is 1: dissolving the mixture in absolute ethyl alcohol according to the molar ratio of 7.5, stirring the mixture for 3 hours at room temperature, carrying out solvothermal reaction for 14 hours at 185 ℃ to obtain a vanadium sulfide precursor, washing the product clean, and freeze-drying the product;

step two: putting vanadium sulfide precursor into argon-hydrogen mixed gas in a tube furnaceHeating to 550 deg.C at a heating rate of 10 deg.C/min under atmosphere, calcining for 4 hr, and grinding to obtain V₂O₃And (3) nanoparticles.

Example 7:

the method comprises the following steps: firstly, mixing sodium metavanadate and thioacetamide according to the ratio of V: s is 1: dissolving the solution with the molar ratio of 8.13 in absolute ethyl alcohol, stirring the solution for 2 hours at room temperature, carrying out solvothermal reaction for 16 hours at 190 ℃ to obtain a vanadium sulfide precursor, washing the product clean, and freeze-drying the product;

step two: heating the vanadium sulfide precursor to 700 ℃ from room temperature at a heating rate of 10 ℃/min in the argon-hydrogen mixed gas atmosphere in a tube furnace, calcining for 4 hours, and grinding to obtain V₂O₃And (3) nanoparticles.