阅读说明：本技术 原位碳复合的α型Mo2C纳米线及其制备方法和应用 (In-situ carbon compounded alpha-Mo2C nanowire and preparation method and application thereof ) 是由 韩春华 张庆勋 安琴友 麦立强 于 2020-05-07 设计创作，主要内容包括：本发明涉及原位碳复合的α型Mo<Sub>2</Sub>C纳米线及其制备方法,其可以应用于钠离子电池负极材料,其直径为100-200nm,长度为5-10μm,由直径10-20nm的Mo<Sub>2</Sub>C纳米颗粒组装而成,在Mo<Sub>2</Sub>C颗粒周围有无定型碳进行包覆。将前驱体材料(C<Sub>6</Sub>H<Sub>5</Sub>NH<Sub>3</Sub>)<Sub>2</Sub>Mo<Sub>3</Sub>O<Sub>10</Sub>2H<Sub>2</Sub>O在H<Sub>2</Sub>/Ar混合气的气氛下利用不同温度煅烧,自然冷却至室温即可得到纳米颗粒组装而成的原位碳复合的α型Mo<Sub>2</Sub>C纳米线。本发明的有益效果是：制备的原位碳复合的α型Mo<Sub>2</Sub>C纳米线用作钠离子电池负极材料,不但表现出优异的储钠容量,而且循环性能和倍率性能也非常杰出。(The invention relates to alpha-Mo compounded by in-situ carbon 2 The C nanowire and the preparation method thereof can be applied to a sodium ion battery cathode material, the diameter of the C nanowire is 100-200nm, the length of the C nanowire is 5-10 mu m, and the C nanowire is made of Mo with the diameter of 10-20nm 2 C nanoparticles of Mo 2 And the periphery of the C particles is coated by amorphous carbon. Mixing the precursor material(C 6 H 5 NH 3 ) 2 Mo 3 O 10 2H 2 O is in H 2 Calcining at different temperatures in the atmosphere of/Ar mixed gas, and naturally cooling to room temperature to obtain the in-situ carbon composite alpha-Mo assembled by nano particles 2 And C, nano wires. The invention has the beneficial effects that: prepared in-situ carbon compounded alpha-type Mo 2 The C nanowire is used as a sodium ion battery cathode material, not only shows excellent sodium storage capacity, but also has excellent cycle performance and rate capability.)

1. In-situ carbon compounded alpha-Mo₂C nano-wire with diameter of 100-200nm and length of 5-10 μm, composed of Mo with diameter of 10-20nm₂C nanoparticles of Mo₂And the periphery of the C particles is coated by amorphous carbon.

2. The in situ carbon of claim 1Composite alpha-type Mo₂Preparation method of C nanowire, precursor material (C)₆H₅NH₃)₂Mo₃O₁₀2H₂O is in H₂Calcining at different temperatures in the atmosphere of/Ar mixed gas, and naturally cooling to room temperature to obtain the in-situ carbon composite alpha-Mo assembled by nano particles₂And C, nano wires.

3. The in-situ carbon-compounded alpha-Mo of claim 2₂The preparation method of the C nanowire is characterized in that the precursor material is obtained by adopting the following preparation method, and comprises the following steps:

1) weighing a certain amount of ammonium molybdate tetrahydrate, stirring and dissolving in deionized water;

2) sequentially adding aniline and hydrochloric acid into the solution obtained in the step 1), and uniformly stirring;

3) heating and stirring the solution obtained in the step 2) in a water bath;

4) centrifuging, washing and drying the solution obtained in the step 3) to obtain the precursor material.

4. The in situ carbon-compounded α -form Mo of claim 2₂The preparation method of the C nanowire is characterized in that the calcination temperature is 500-700 ℃, the time is 2-5h, and the heating rate is 5 ℃/min.

5. The in situ carbon-compounded α -form Mo of claim 3₂The preparation method of the C nanowire is characterized in that the mass of the ammonium molybdate tetrahydrate in the step 1) is 1.24-4.15g, the molar ratio of the aniline added in the step 2) to the ammonium molybdate tetrahydrate is 15-18:1, then hydrochloric acid with the concentration of 1mol/L is added to adjust the pH value to be 4-5, and the stirring is carried out for 5 min.

6. The in situ carbon-compounded α -form Mo of claim 3₂The preparation method of the C nanowire is characterized in that the water bath temperature in the step 3) is 40-80 ℃, and the time is 6-10 h.

7. The in situ carbon-compounded α -form Mo of claim 3₂The preparation method of the C nanowire is characterized in that the precipitate is washed for 5 times by the washing in the step 4), and the drying temperature is 80 ℃ and the time is 12 hours.

8. The in-situ carbon-composited alpha-Mo of claim 1₂The application of the C nanowire as a negative active material of a sodium ion battery.

Technical Field

The invention belongs to the technical field of nano materials and electrochemical energy conversion, and particularly relates to in-situ carbon compounded alpha-Mo₂The C nanowire and the preparation method thereof can be applied to a sodium ion battery cathode material.

Background

With the rapid development of society and economy in China, the requirement of energy requires that green energy has to be further developed, and a lithium ion battery is used as a good energy storage device and widely applied to electronic digital products such as mobile phones, notebook computers and the like, and particularly, the development of new energy automobiles leads people to find an effective way for reducing environmental pollution; however, the storage capacity of lithium element on the earth is low, so that the lithium element cannot meet the future requirements on new energy automobiles and cannot meet the future requirements on preparing large-scale energy storage devices with low cost and excellent performance; however, sodium element is abundant in the earth and low in cost, so that sodium ion batteries become a great hot spot for research. At present, the cathode materials of the sodium ion battery can be mainly classified into three types according to the reaction mechanism: an embedded negative electrode material, an alloying material, and a conversion reaction material; however, these materials often have the problems of poor cycling stability, poor rate capability, large volume expansion and the like, so it is important to develop a sodium ion battery cathode material with low price, high capacity, good cycling performance and good rate capability.

In recent years, transition metal carbides have been widely used in catalysis, electrochemical energy storage, and the like due to their good hardness, chemical stability, and electrical conductivity. Among them, molybdenum carbide has good lithium and sodium storage properties due to its good conductivity and high hardness, but for in-situ carbon-compounded alpha-Mo₂The research on the C nanowire as sodium storage is less.

Disclosure of Invention

Aiming at the prior technical problems, the invention provides the alpha-Mo compounded by the in-situ carbon₂The preparation method of the C nanowire is simple in process and high in feasibility, and prepares the C nanowireThe cathode material of the sodium ion battery has good cycle stability, high multiplying power and other electrochemical properties.

The technical scheme adopted by the invention for solving the technical problems is as follows: in-situ carbon compounded alpha-Mo₂C nano-wire with diameter of 100-200nm and length of 5-10 μm, composed of Mo with diameter of 10-20nm₂C nanoparticles of Mo₂And the periphery of the C particles is coated by amorphous carbon.

The in-situ carbon compounded alpha-Mo₂Preparation method of C nanowire, precursor material (C)₆H₅NH₃)₂Mo₃O₁₀2H₂O is in H₂Calcining at different temperatures in the atmosphere of/Ar mixed gas, and naturally cooling to room temperature to obtain the in-situ carbon composite alpha-Mo assembled by nano particles₂And C, nano wires.

According to the scheme, the precursor material is obtained by adopting the following preparation method, and comprises the following steps:

1) weighing a certain amount of ammonium molybdate tetrahydrate, stirring and dissolving in deionized water;

2) sequentially adding aniline and hydrochloric acid into the solution obtained in the step 1), and uniformly stirring;

3) heating and stirring the solution obtained in the step 2) in a water bath;

4) centrifuging, washing and drying the solution obtained in the step 3) to obtain the precursor material.

According to the scheme, the calcination temperature is 500-700 ℃, the time is 2-5h, and the heating rate is 5 ℃/min.

According to the scheme, the mass of the ammonium molybdate tetrahydrate in the step 1) is 1.24-4.15g, the molar ratio of the aniline added in the step 2) to the ammonium molybdate tetrahydrate is 15-18:1, then hydrochloric acid with the concentration of 1mol/L is added to adjust the pH value to be 4-5, and the mixture is stirred for 5 min.

According to the scheme, the temperature of the water bath in the step 3) is 40-80 ℃, and the time is 6-10 h.

According to the scheme, the precipitate is washed for 5 times by the washing in the step 4), and the drying temperature is 80 ℃ and the time is 12 hours.

The in-situ carbon compounded alpha-Mo₂The application of the C nanowire as a negative active material of a sodium ion battery.

The reaction mechanism of the invention is as follows: dissolving soluble ammonium molybdate tetrahydrate in deionized water, and reacting aniline and molybdate radical in acidic environment to generate precursor material (C)₆H₅NH₃)₂Mo₃O₁₀2H₂O, the precursor material is firstly carbonized and MoO is generated at the temperature rise₃Carbon material and H at high temperature calcination₂Under reduction of (2) MoO₃Will be reduced into alpha-Mo₂C。

The invention has the beneficial effects that: the method synthesizes the in-situ carbon compounded alpha-Mo through water bath stirring and solid-phase sintering₂The nanowire material has larger specific surface area and more reactive active sites, so that the nanowire material has better sodium storage performance, reduces the diffusion distance of ions and is beneficial to rapid ion migration; the carbon material can increase the conductivity to facilitate the electron conduction on one hand, and can prevent the nano wire from agglomerating on the other hand, so that the dispersibility of the nano wire is better. Compounding the prepared in-situ carbon with alpha-type Mo₂The C nanowire is used as a sodium ion battery cathode material, not only shows excellent sodium storage capacity, but also has excellent cycle performance and rate capability.

Drawings

FIG. 1 shows in-situ carbon-compounded α -Mo in example 1 of the present invention₂XRD spectrum of the C nanowire;

FIG. 2 shows in-situ carbon-compounded α -Mo in example 1 of the present invention₂SEM atlas of C nanowire;

FIG. 3 shows in-situ carbon-compounded α -Mo in example 1 of the present invention₂Raman spectrum of the C nanowire;

FIG. 4 shows in-situ carbon-compounded α -Mo in example 1 of the present invention₂A CV diagram of the C nanowire as a sodium ion battery cathode material;

FIG. 5 shows in-situ carbon-compounded α -Mo in example 1 of the present invention₂C nanowire as sodium ion battery negative electrode materialThe material is at 1A g^-1A battery cycle performance plot at current density;

FIG. 6 shows in-situ carbon-compounded α -Mo in example 1 of the present invention₂The C nanowire is used as a battery rate performance diagram of the sodium ion battery cathode material under different current densities;

detailed description of the preferred embodiments

For a better understanding of the present invention, the following examples are set forth to illustrate, but are not to be construed as the limit of the present invention.