阅读说明：本技术 一种B或V掺杂的Zn2GeO4纳米材料及其制备方法 (Zn doped with B or V2GeO4Nano material and preparation method thereof ) 是由 曹阳 王利霞 方华 张勇 于 2021-09-17 设计创作，主要内容包括：本发明涉及一种B或V掺杂的Zn-(2)GeO-(4)纳米材料及其制备方法,将GeO-(2)和Tris溶解在溶剂中,搅拌形成透明均一的Ge-Tris溶液；向Ge-Tris溶液中加入硼酸或者氯化钒,搅拌,再加入乙二醇和锌盐,搅拌均匀；将所得到的溶液进行水热反应,反应结束后自然冷却至室温,过滤,干燥,即得B或V掺杂的Zn-(2)GeO-(4)纳米材料。本发明采用水热法制备B或V掺杂的Zn-(2)GeO-(4)纳米材料,尺寸可控,分散性较好,电子传输性能优异,作为新型锂电池的负极材料等应用方面有着优异的性能,具有较高的工业生产价值。(The invention relates to a Zn doped with B or V 2 GeO 4 Nano material prepared from GeO and its preparing process 2 Dissolving Tris and the solvent, and stirring to form a transparent and uniform Ge-Tris solution; adding boric acid or vanadium chloride into the Ge-Tris solution, stirring, adding ethylene glycol and zinc salt, and uniformly stirring; carrying out hydrothermal reaction on the obtained solution, naturally cooling to room temperature after the reaction is finished, filtering and drying to obtain B or V doped Zn 2 GeO 4 And (3) nano materials. The invention adopts a hydrothermal method to prepare Zn doped with B or V 2 GeO 4 The nano material has controllable size, better dispersibility and excellent electron transmission performance, and is used as a novel lithium batteryThe cathode material and the like have excellent performance in the application aspect and have higher industrial production value.)

1. Zn doped with B or V₂GeO₄The preparation method of the nano material is characterized in that B or V element is added into a mixed solution of Ge-Tris and zinc salt to obtain a reaction solution, the obtained reaction solution is subjected to hydrothermal reaction and then is kept stand for cooling, separated and dried to obtain B or V doped Zn₂GeO₄The nano material specifically comprises the following steps:

(1) adding GeO₂Dissolving Tris and the solvent, and stirring to form a transparent and uniform Ge-Tris solution;

(2) adding boric acid or vanadium chloride into the Ge-Tris solution, stirring, adding ethylene glycol and zinc salt, and uniformly stirring;

(3) carrying out hydrothermal reaction on the solution obtained in the step (2), naturally cooling to room temperature after the reaction is finished, filtering and drying to obtain B or V doped Zn₂GeO₄And (3) nano materials.

2. B or B according to claim 1V-doped Zn₂GeO₄The preparation method of the nano material is characterized in that the step (1) is that GeO is contained in Ge-Tris solution₂The concentration of the Tris is 0.1-10mmol/L, the concentration of the Tris is 0.5-50mmol/L, and the reaction time is 0.1-5h under stirring at room temperature.

3. B or V doped Zn according to claim 2₂GeO₄The preparation method of the nano material is characterized in that the step (1) is that GeO is contained in Ge-Tris solution₂The molar ratio to Tris was 1: 1.

4. B or V doped Zn according to claim 1₂GeO₄The preparation method of the nano material is characterized in that one or more of solvents of water, methanol and ethanol in the step (1) are adopted.

5. B or V doped Zn according to claim 1₂GeO₄The preparation method of the nano material is characterized in that the zinc salt in the step (2) is one or more of zinc acetate, zinc nitrate and zinc chloride.

6. B or V doped Zn according to claim 1₂GeO₄The preparation method of the nano material is characterized in that the zinc salt and GeO in the step (2)₂In a molar ratio of 2:1, boric acid or vanadium chloride and GeO₂The molar ratio of (0.01-0.1) to (1).

7. B or V doped Zn according to claim 1₂GeO₄The preparation method of the nano material is characterized in that the temperature of the hydrothermal reaction in the step (3) is 100-180 ℃, and the reaction time is 1-10 h.

8. B or V doped Zn according to claim 1₂GeO₄The preparation method of the nano material is characterized in that the drying temperature in the step (3) is 40-70 ℃.

9. B or V doped Zn prepared by the method of any one of claims 1 to 8₂GeO₄And (3) nano materials.

10. B or V doped Zn according to claim 9₂GeO₄The nanometer material is characterized in that the particle size of the nanometer material is 50-100 nm.

Technical Field

The invention relates to a Zn doped with B or V₂GeO₄Nano material and preparation thereofThe method belongs to the technical field of electrode materials of energy storage devices.

Background

Currently, the world energy consumption mainly comes from non-renewable energy sources such as coal, oil and natural gas, but with the global diminishing non-renewable energy sources, the development and utilization of new energy sources are slow. The lithium ion battery is a novel chemical energy source which is started in the 90 th of the 20 th century, and has the characteristics of large specific capacity, good cycle performance, high working voltage, long service life, small pollution and the like. Among them, energy storage devices such as lithium ion batteries have many advantages such as large energy density, high power density, long cycle life, low self-discharge rate and "green" environmental protection, and become a hotspot of application.

With the increasingly wide application fields of energy storage devices such as lithium ion batteries and the like, the performance requirements of the application fields on the energy storage devices such as the lithium ion batteries and the like are also increasingly high, however, due to the self limitation of the energy storage devices such as the lithium ion batteries and the like, the performance improvement of the energy storage devices meets a larger bottleneck, and the bottleneck of the performance of the electrode material is a key factor for restricting the performance improvement of the energy storage devices such as the lithium ion batteries and the like. Therefore, the development of a novel high-performance electrode material is significant for solving the performance bottleneck of energy storage devices such as lithium ion batteries.

Germanium-based materials are considered to be promising lithium ion negative electrode materials due to their high theoretical capacity, and thus have been the focus of research. However, the huge volume expansion of the material in the charging and discharging process can cause the electrode material to be pulverized, collapsed and the conductivity to be reduced, and finally the electrode material has lower reversible capacity and poorer cycle performance, thereby influencing the practical application of the electrode material. Therefore, solving the problems of volume expansion and conductivity of the electrode material in the charging and discharging process is the key for determining whether the electrode material has application value.

Zn₂GeO₄The lithium ion battery cathode material has the advantages of high theoretical specific capacity, rich raw material resources, relatively low price and the like, and has wide application prospect when being used as a cathode material of energy storage devices such as a lithium ion battery and the like. The defects of low first coulombic efficiency, poor cycle stability, poor rate capability and the like are also faced, so that the doped Zn is prepared₂GeO₄The above problems can be solved to some extent.

Disclosure of Invention

The invention aims to provide a method for preparing Zn doped with B or V₂GeO₄A method for preparing nano material.

The invention also aims to provide the Zn doped with B or V prepared by the method₂GeO₄And (3) nano materials.

B or V doped Zn for solving the technical problems₂GeO₄The preparation method of the nano material comprises the following steps: adding B or V element into a mixed solution of Ge-Tris and zinc salt to obtain a reaction solution, carrying out hydrothermal reaction on the obtained reaction solution, standing, cooling, separating and drying to obtain B or V doped Zn₂GeO₄The nano material specifically comprises the following steps:

(1) adding GeO₂And Tris (Tris hydroxymethyl aminomethane) are dissolved in the solvent and stirred to form a transparent and uniform Ge-Tris solution;

(2) adding boric acid or vanadium chloride into the Ge-Tris solution, stirring, adding ethylene glycol and zinc salt, and uniformly stirring;

(3) carrying out hydrothermal reaction on the solution obtained in the step (2), naturally cooling to room temperature after the reaction is finished, filtering and drying to obtain B or V doped Zn₂GeO₄And (3) nano materials.

Further, the step (1) is GeO in Ge-Tris solution₂The concentration of the Tris is 0.1-10mmol/L, the concentration of the Tris is 0.5-50mmol/L, and the reaction time is 0.1-5h under stirring at room temperature.

Further, the step (1) is GeO in Ge-Tris solution₂The molar ratio to Tris was 1: 1.

Further, in the step (1), one or more of solvents of water, methanol and ethanol.

Further, the zinc salt in the step (2) is one or more of zinc acetate, zinc nitrate and zinc chloride.

Further, the zinc salt and GeO in the step (2)₂In a molar ratio of 2:1, boric acid or chlorinationVanadium and GeO₂The molar ratio of (0.01-0.1) to (1).

Further, the volume ratio of the ethylene glycol in the step (2) to the solvent in the step (1) is (0.1-10): 1.

Further, the temperature of the hydrothermal reaction in the step (3) is 100-.

Further, the drying temperature in the step (3) is 40-70 ℃.

B or V doped Zn prepared by the preparation method₂GeO₄Nano material, the grain diameter of the obtained nano material is 50-100 nm.

The invention has the beneficial effects that: b-or V-doped Zn of the invention₂GeO₄Method for preparing material Zn is prepared by using hydrothermal reaction method₂GeO₄Adding doping elements into a precursor solution of hydrothermal reaction to obtain doped Zn₂GeO₄A material. The method has the characteristics of simple preparation method, low process cost and low energy consumption, and is very suitable for industrial application.

B-or V-doped Zn of the invention₂GeO₄The material prepared by the preparation method can be used as the cathode material of energy storage devices such as lithium ion batteries and the like, wherein B or V is doped with Zn₂GeO₄The material particles store charges through electrochemical reaction, and the doping material is beneficial to free migration of electrolyte ions, so that the advantages of a hollow structure are fully exerted, and the negative electrode material of energy storage devices such as lithium ion batteries and the like with high power density and high energy density is obtained.

Drawings

FIG. 1 shows a B-or V-doped Zn of example 1 of the present invention₂GeO₄Material and Zn₂GeO₄An XRD pattern of (a);

FIG. 2 shows a B-or V-doped Zn according to example 1 of the present invention₂GeO₄Material and Zn₂GeO₄SEM image of (a-Zn)₂GeO₄B-B doped Zn₂GeO₄Material, c-V doped Zn₂GeO₄Material);

FIG. 3 is a B or V doped Zn of example 1 of the present invention₂GeO₄Element doping mapping graph of the material;

FIG. 4 is a B or V doped Zn of example 1 of the present invention₂GeO₄Material and Zn₂GeO₄As the first charge-discharge curve of the lithium ion battery cathode material;

FIG. 5 is a B or V doped Zn of example 1 of the present invention₂GeO₄Material and Zn₂GeO₄And (4) taking the obtained product as a cycle rate curve of the lithium ion battery cathode material.

Detailed Description

The present invention will be further described with reference to the following examples. It is to be understood that the following examples are illustrative only and are not intended to limit the scope of the invention, which is to be given numerous insubstantial modifications and adaptations by those skilled in the art based on the teachings set forth above.

Example 1

Zn doped with B or V of the present example₂GeO₄The preparation method of the material comprises the following steps:

1) 0.5mmol of GeO was slowly added to 30mL of water₂Stirring the mixture and 0.5mmol of Tris until a uniform and transparent solution is formed, and finishing the reaction;

2) taking the solution prepared in the step 1), and respectively adding 10ml of ethylene glycol and 1mmol of ZnCl into the solution under stirring₂Then adding 5mol% (as GeO)₂Reference) or vanadium chloride, stirring, putting the solution obtained by the reaction into a reaction kettle, placing the reaction kettle into a 160 ℃ oven, reacting for 3 hours, naturally cooling to room temperature, centrifuging, washing with distilled water, and drying the solid obtained by the reaction in a 70 ℃ oven to obtain the product.

Example 2

Zn doped with B or V of the present example₂GeO₄The preparation method of the material comprises the following steps:

1) 0.5mmol of GeO was slowly added to 30mL of water₂And 0.5mmol of Tris was stirred until a uniform and transparent solution was formed, and the reaction was terminated.

2) Taking step1) Adding 10ml of ethylene glycol and 1mmol of ZnCl into the solution under stirring₂Then adding 5mol% (as GeO)₂Reference) or vanadium chloride, stirring, putting the solution obtained by the reaction into a reaction kettle, placing the reaction kettle into a 120 ℃ oven, reacting for 5 hours, naturally cooling to room temperature, centrifuging, washing with distilled water, and drying the solid obtained by the reaction in a 70 ℃ oven to obtain the product.

Example 3

Zn doped with B or V of the present example₂GeO₄The preparation method of the material comprises the following steps:

1) 0.5mmol of GeO was slowly added to 20mL of water₂And 0.5mmol of Tris was stirred until a uniform and transparent solution was formed, and the reaction was terminated.

2) Taking the solution prepared in the step 1), adding 20ml of ethylene glycol and 1mmol of Zn (AC) respectively under stirring₂Then adding 5mol% (as GeO)₂Reference) or vanadium chloride, stirring, putting the solution obtained by the reaction into a reaction kettle, placing the reaction kettle into a 120 ℃ oven, reacting for 5 hours, naturally cooling to room temperature, centrifuging, washing with distilled water, and drying the solid obtained by the reaction in a 70 ℃ oven to obtain the product.

Example 4

Zn doped with B or V of the present example₂GeO₄The preparation method of the material comprises the following steps:

1) 0.5mmol of GeO was slowly added to 20mL of water₂And 0.5mmol of Tris was stirred until a uniform and transparent solution was formed, and the reaction was terminated.

2) Taking the solution prepared in the step 1), adding 20ml of ethylene glycol and 1mmol of Zn (AC) respectively under stirring₂Then adding 10 mol% (as GeO)₂Reference) or vanadium chloride, stirring, putting the solution obtained by the reaction into a reaction kettle, placing the reaction kettle into a 160 ℃ oven, reacting for 3 hours, naturally cooling to room temperature, centrifuging, washing with distilled water, and drying the solid obtained by the reaction in a 70 ℃ oven to obtain the product.

Example 5

Zn doped with B or V of the present example₂GeO₄The preparation method of the material comprises the following steps:

1) 0.5mmol of GeO was slowly added to 30mL of water₂And 0.5mmol of Tris was stirred until a uniform and transparent solution was formed, and the reaction was terminated.

2) Taking the solution prepared in the step 1), and respectively adding 10ml of ethylene glycol and 1mmol of ZnCl into the solution under stirring₂Then adding 1 mol% (as GeO)₂Reference) or vanadium chloride, stirring, putting the solution obtained by the reaction into a reaction kettle, placing the reaction kettle into a 180 ℃ oven, reacting for 1h, naturally cooling to room temperature, centrifuging, washing with distilled water, and drying the solid obtained by the reaction in a 70 ℃ oven to obtain the product.

Test examples

1) Phase testing

Zn is obtained in example 1₂GeO₄And B, V-doped Zn₂GeO₄XRD detection is carried out on the material, and the result is shown in figure 1.

The diffraction peaks appeared on the map at positions of 12.4 ° (110), 21.6 ° (300), 24.9 ° (220), 30.8 ° (113), 33.3 ° (410), 37.9 ° (223), 47.8 ° (333), 58 ° (006), 64.1 ° (713), and 68.5 ° (416), and the positions of the peaks all correspond to standard Zn (110), 21.6 ° (300), 24.9 ° (220), 30.8 ° (113), 33.3 ° (410), 37.9 ° (223), 47.8 ° (333), 58 ° (006), 64.1 ° (713), and 68.5 ° (416)₂GeO₄（PDF#11-0687）。

2) Topography testing

Zn obtained in example 1₂GeO₄And B, V-doped Zn₂GeO₄SEM and mapping tests were performed on the materials, and the results are shown in FIG. 2 and FIG. 3, respectively.

As can be seen from FIG. 2, the prepared particles have a particle size of 50-100nm and a uniform particle size. From the mapping graph, the doping element distribution can be found to be uniform.

3) Electrochemical performance test

Zn doped with B or V prepared in example 1₂GeO₄Material and Zn₂GeO₄As the negative electrode material of the lithium ion battery, a lithium sheet is taken as a counter electrode to prepare 2016 type lithium ionAnd (4) a pool.

Example 1 preparation of B or V doped Zn₂GeO₄Material and Zn₂GeO₄As a lithium ion battery cathode material, the first discharge capacities at a charge-discharge rate of 100mAh/g are 1085 mAh/g, 1406 mAh/g and 1372mAh/g respectively. The test results are shown in fig. 4.

The charge and discharge were performed at 100mAh/g, 200mAh/g, 500mAh/g, 1000mAh/g, and 100mAh/g, respectively, and a cycle test was performed, and the test results are shown in FIG. 5.

The foregoing shows and describes the general principles and features of the present invention, together with the advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.