阅读说明：本技术 一种柔性自支撑二硒化锡/碳纳米管复合薄膜电极材料及其制备方法和应用 (Flexible self-supporting tin diselenide/carbon nano tube composite film electrode material and preparation method and application thereof ) 是由 孙志鹏 吴方丹 邵涟漪 方路峻 史晓艳 余锦超 张海峰 于 2019-09-19 设计创作，主要内容包括：本发明属于钠离子电池材料领域,公开了一种柔性自支撑二硒化锡/碳纳米管复合薄膜电极材料及其制备方法和应用。所述柔性自支撑二硒化锡/碳纳米管复合薄膜电极材料是将碳纳米管和乙二醇超声混合,得到混合溶液A；再加入乙二胺搅拌混合,得到混合溶液B；再将二硒化锡和硒粉加入到混合溶液B中搅拌,得到混合溶液C,将混合溶液C在150～220℃下进行水热反应,将产物经真空抽滤和冲洗,在40～80℃干燥后制得。本发明制备简单,成本低且污染小,该复合薄膜电极材料具有层状薄膜结构,柔韧性好,微纳形貌,孔结构丰富,具有无导电剂和粘结剂、比容量较高、倍率较好和循环稳定性较优的特点,可用于钠离子电池电极。(The invention belongs to the field of sodium ion battery materials, and discloses a flexible self-supporting tin diselenide/carbon nano tube composite film electrode material, and a preparation method and application thereof. The flexible self-supporting tin diselenide/carbon nano tube composite film electrode material is prepared by ultrasonically mixing a carbon nano tube and ethylene glycol to obtain a mixed solution A; adding ethylenediamine, stirring and mixing to obtain a mixed solution B; and adding tin diselenide and selenium powder into the mixed solution B, stirring to obtain a mixed solution C, carrying out hydrothermal reaction on the mixed solution C at the temperature of 150-220 ℃, carrying out vacuum filtration and washing on a product, and drying at the temperature of 40-80 ℃ to obtain the product. The composite film electrode material has the characteristics of layered film structure, good flexibility, micro-nano morphology, rich pore structure, no conductive agent and binder, high specific capacity, high multiplying power and high cycling stability, and can be used for sodium ion battery electrodes.)

1. A flexible self-supporting tin diselenide/carbon nano tube composite film electrode material is characterized in that the flexible self-supporting tin diselenide/carbon nano tube composite film electrode material is prepared by mixing carbon nano tubes and ethylene glycol in an ultrasonic mode to obtain a mixed solution A; adding ethylenediamine, stirring and mixing to obtain a mixed solution B; and adding tin diselenide and selenium powder into the mixed solution B, stirring to obtain a mixed solution C, carrying out hydrothermal reaction on the mixed solution C at the temperature of 150-220 ℃, carrying out vacuum filtration and washing on a product, and drying at the temperature of 40-80 ℃ to obtain the product.

2. The flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material as claimed in claim 1, wherein the concentration of the mixed solution A is 0.4-1.5 mg/ml, and the concentration of the mixed solution B is 0.4-2 mg/ml.

3. The flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material as claimed in claim 1, wherein the volume ratio of ethylene glycol to ethylenediamine is 1: (10-20).

4. The flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material of claim 1, wherein the carbon nanotubes are one or more of aminated single-walled carbon nanotubes, double-walled carbon nanotubes or multi-walled carbon nanotubes.

5. The flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material as claimed in claim 1, wherein the concentration of tin diselenide in the solution C is 2.5-4 mg/ml, and the molar ratio of the selenium powder to the tin diselenide is (1.5-2.7): 1.

6. the flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material as claimed in claim 1, wherein the hydrothermal reaction time is 18-30 h; the drying time is 5-8 h.

7. The flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material as claimed in claim 1, wherein the power of the ultrasound is 400-900W, the frequency of the ultrasound is 10-25 kHz, and the time of the ultrasound is 30-60 min.

8. The flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material as claimed in claim 1, wherein the reagents for suction filtration and washing are deionized water and absolute ethyl alcohol.

9. The preparation method of the flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material according to any one of claims 1 to 8, which is characterized by comprising the following specific steps of:

s1, ultrasonically mixing a carbon nano tube and ethylene glycol to obtain a mixed solution A;

s2, adding ethylenediamine into the mixed solution A, and stirring and mixing to obtain a mixed solution B;

s3, adding tin diselenide and selenium powder into the mixed solution B, and uniformly stirring to obtain a mixed solution C;

and S4, carrying out hydrothermal reaction on the mixed solution C at the temperature of 150-220 ℃, carrying out vacuum filtration and washing on a product, and drying at the temperature of 40-80 ℃ to obtain the flexible self-supporting tin diselenide/carbon nano tube composite film electrode material.

10. The use of the flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material of any one of claims 1 to 8 in the field of sodium ion batteries or energy storage.

Technical Field

The invention belongs to the technical field of sodium ion battery materials, and particularly relates to a flexible self-supporting tin diselenide/carbon nano tube composite film electrode material and a preparation method and application thereof.

Background

The tin diselenide is a semiconductor material and has excellent optical and electrical properties, and the flaky tin diselenide has a lamellar structure, has the advantages of safety, environmental protection, stable cycle performance and the like, and can be used as a cathode material of a sodium ion battery. At present, the method for preparing the cathode material of the tin diselenide sodium ion battery is mainly a liquid phase method. Pengherin et al discloses a preparation method of a nano tin diselenide powder material, which adopts sodium selenite as a selenium source, ethylene glycol as a solvent and ethylenediamine as an auxiliary solvent, and a hydrothermal reaction is carried out in a high-pressure reaction kettle to obtain the tin diselenide nanosheets. The preparation process mostly needs hydrazine hydrate as an auxiliary material, the hydrazine hydrate is a virulent substance, is not friendly to human bodies and environment, and has complex preparation process and higher cost, thus not meeting the requirement of large-scale industrial production. And the pure tin diselenide material has poor electrochemical performance and severe attenuation of battery capacity.

Therefore, the pure tin diselenide material can be modified to slow down the volume expansion, slow down the capacity attenuation and improve the electrochemical performance. Meanwhile, the simplified process is considered, and toxic materials such as hydrazine hydrate and the like are replaced by environment-friendly and nontoxic medicines. The carbon nano tube is a common carbon material, has a fiber structure, is uniformly coated on the surface of the tin diselenide material, can improve the conductivity, and simultaneously slows down the volume expansion, so that the problem of capacity attenuation is overcome to a certain extent by pure tin diselenide. And the carbon nano tube material is non-toxic and harmless and is friendly to human and environment.

After the tin diselenide is compounded with the carbon nano tube, if the original process is used, namely the tin diselenide/carbon nano tube material is used in combination with a conductive agent and a bonding agent, the process is still complex, and the cost is higher. If the use of conductive agents and binders can be reduced or eliminated while maintaining good electrochemical performance, the cost can be greatly reduced and the requirements of industrial production can be met. The flexible self-supporting material can be used for mounting the battery without matching with a conductive agent and a binder, and has the advantages of simple process, low cost and good application prospect.

Disclosure of Invention

In order to overcome the defects and shortcomings of the prior art, the invention aims to provide a flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material.

The invention also aims to provide a preparation method of the flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material.

The invention also aims to provide application of the flexible self-supporting tin diselenide/carbon nanotube composite thin film electrode material.

The purpose of the invention is realized by the following technical scheme:

a flexible self-supporting tin diselenide/carbon nano tube composite film electrode material is prepared by ultrasonically mixing a carbon nano tube and ethylene glycol to obtain a mixed solution A; adding ethylenediamine, stirring and mixing to obtain a mixed solution B; and adding tin diselenide and selenium powder into the mixed solution B, stirring to obtain a mixed solution C, carrying out hydrothermal reaction on the mixed solution C at the temperature of 150-220 ℃, carrying out vacuum filtration and washing on a product, and drying at the temperature of 40-80 ℃ to obtain the product.

Preferably, the concentration of the mixed solution A is 0.4-1.5 mg/ml, and the concentration of the mixed solution B is 0.4-2 mg/ml.

Preferably, the volume ratio of ethylene glycol to ethylene diamine is 1: (10-20).

Preferably, the carbon nanotube is one or more of an aminated single-walled carbon nanotube, a double-walled carbon nanotube or a multi-walled carbon nanotube.

Preferably, the concentration of tin diselenide in the solution C is 2.5-4 mg/ml, and the molar ratio of the selenium powder to the tin diselenide is (1.5-2.7): 1.

preferably, the time of the hydrothermal reaction is 18-30 h; the drying time is 5-8 h.

Preferably, the power of the ultrasound is 400-900W, the frequency of the ultrasound is 10-25 kHz, and the time of the ultrasound is 30-60 min.

Preferably, the reagents for suction filtration and washing are deionized water and absolute ethyl alcohol.

The preparation method of the flexible self-supporting tin diselenide/carbon nano tube composite film electrode material comprises the following specific steps:

s1, ultrasonically mixing a carbon nano tube and ethylene glycol to obtain a mixed solution A;

s2, adding ethylenediamine into the mixed solution A, and stirring and mixing to obtain a mixed solution B;

s3, adding tin diselenide and selenium powder into the mixed solution B, and uniformly stirring to obtain a mixed solution C;

and S4, carrying out hydrothermal reaction on the mixed solution C at the temperature of 150-220 ℃, carrying out vacuum filtration and washing on a product, and drying at the temperature of 40-80 ℃ to obtain the flexible self-supporting tin diselenide/carbon nano tube composite film electrode material.

The flexible self-supporting tin diselenide/carbon nano tube composite film electrode material is applied to the field of sodium ion batteries or energy storage.

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

1. the tin diselenide/carbon tube composite film material has a film-shaped structure, is good in flexibility, can be bent for multiple times, has a small-diameter and uniformly-distributed tin diselenide laminated structure, and the carbon tube is uniformly coated on the surface of the tin diselenide material. The characteristics of nano size, lamellar structure and thin film structure effectively improve the reaction area of ions, and the carbon tube is coated to ensure that the capacity is not attenuated or is attenuated little during charging and discharging; the addition of the carbon tube further improves the surface conductivity of the material, and obviously improves the rate capability and the cycle performance of the material.

2. The reaction raw materials of the carbon nano tube, the tin diselenide, the ethylene glycol, the ethylenediamine and the selenium powder used in the invention have the characteristics of low price, low risk and wide sources, and are obviously superior to the hazardous chemical materials which are easy to poison or explode and are used in the prior similar technology.

3. The invention can obtain the flexible self-supporting tin diselenide/carbon nano tube composite film electrode material by controlling the reaction conditions, the obtained film composite material has small thickness of lamina, larger surface area and two-dimensional lamina structure, can effectively improve the transmission rate of ions, ensures that the charge and discharge capacity is not attenuated, and the material capacity is attenuated by adding the carbon tube.

4. The flexible self-supporting tin diselenide/carbon nano tube composite film electrode material can be directly used as a sodium ion battery electrode, and does not need to use a binder and a conductive agent, so that the experimental cost is reduced, the production period is shortened, and the application range of the material in other fields is enlarged.

5. In the process of the flexible self-supporting tin diselenide/carbon nano tube composite film electrode material, the reaction conditions are mild, the control is convenient, the operation is simple, the production cost is low, and the industrial production is easy to realize.

Drawings

Fig. 1 is an XRD pattern of tin diselenide/carbon nanotube thin film composite material prepared in examples 1-3.

Fig. 2 is an SEM photograph of tin diselenide/carbon nanotube thin film composites obtained in examples 1-3 and pure tin diselenide.

FIG. 3 is a constant current cycle chart of the tin diselenide/carbon nanotube thin film composite material prepared in examples 1-3 at a current density of 0.1A/g.

Fig. 4 is a rate performance curve of tin diselenide/carbon nanotube thin film composite materials prepared in examples 1-3.

Fig. 5 is a diagram of a tin diselenide/carbon nanotube thin film composite material prepared in example 1.

Detailed Description

The following examples are presented to further illustrate the present invention and should not be construed as limiting the invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated. Unless otherwise indicated, reagents and materials used in the following examples are commercially available.