阅读说明：本技术 用于制备碳纤维材料的纺丝液、柔性电极材料以及制备方法 (Spinning solution for preparing carbon fiber material, flexible electrode material and preparation method ) 是由 赖超 孙闯 于 2020-03-23 设计创作，主要内容包括：本发明公开了一种用于制备碳纤维材料的纺丝液,包括：聚乙烯吡咯烷酮、冰乙酸、硅酸四乙酯、钛酸四丁酯以及有机溶剂。在前述基础上,本发明还公开了一种柔性电极材料以及柔性电极材料的制备方法。利用本发明的纺丝液制备的柔性电极材料具有空心结构,能够实现优良的机械性能与优异的电化学性能。(The invention discloses a spinning solution for preparing a carbon fiber material, which comprises the following components: polyvinylpyrrolidone, glacial acetic acid, tetraethyl silicate, tetrabutyl titanate and organic solvents. On the basis of the above, the invention also discloses a flexible electrode material and a preparation method of the flexible electrode material. The flexible electrode material prepared by the spinning solution has a hollow structure, and can realize excellent mechanical property and excellent electrochemical property.)

1. A dope for preparing a carbon fiber material, comprising:

polyvinylpyrrolidone, a catalyst, tetraethyl silicate, tetrabutyl titanate and an organic solvent.

2. The dope of claim 1, wherein the catalyst is glacial acetic acid.

3. The spinning dope of claim 1, comprising:

5-15 parts of polyvinylpyrrolidone;

5-15 parts of catalyst;

tetraethyl silicate, 15-25 parts by weight;

2-8 parts of tetrabutyl titanate;

40-60 parts of organic solvent.

4. The spinning dope of claim 3, comprising:

9-11 parts of polyvinylpyrrolidone;

9-11 parts of catalyst;

tetraethyl silicate, 18-22 parts by weight;

4-6 parts of tetrabutyl titanate;

50-60 parts of organic solvent.

5. The dope of claim 1, further comprising a nanomaterial comprising at least one of a one-dimensional nanomaterial and a two-dimensional nanomaterial; the addition amount of the nano material is 0.1-1 part by weight based on 100 parts by weight of the spinning solution.

6. The spinning dope of claim 5, wherein the one-dimensional nanomaterial comprises at least one of carbon nanotubes and metal nanowires; the metal nanowires are VIII, IB and IIIA group metal nanowires;

the two-dimensional nano material at least comprises one of graphene oxide, two-dimensional transition metal carbide and two-dimensional transition metal nitride.

7. The dope according to any one of claims 1 to 6, wherein the organic solvent comprises at least one of absolute ethanol, N-methylpyrrolidone, dimethylformamide and dimethylacetamide.

8. A flexible electrode material prepared from the spinning dope of any one of claims 1 to 7.

9. A preparation method of a flexible electrode material is characterized by comprising the following steps:

adding polyvinylpyrrolidone and glacial acetic acid into an organic solvent, uniformly stirring, and then adding tetraethyl silicate and tetrabutyl titanate to prepare a spinning solution;

carrying out electrostatic spinning on the spinning solution to prepare spinning fibers;

and (3) carrying out activation hydrolysis on the spinning fiber, then introducing inert gas and sintering at the temperature of 400-800 ℃ to prepare the flexible electrode material.

10. A preparation method of a flexible electrode material is characterized by comprising the following steps:

adding polyvinylpyrrolidone, glacial acetic acid and nano materials into an organic solvent, uniformly stirring, and then adding tetraethyl silicate and tetrabutyl titanate to prepare a spinning solution;

carrying out electrostatic spinning on the spinning solution to prepare spinning fibers;

and (3) carrying out activation hydrolysis on the spinning fiber, then introducing inert gas and sintering at the temperature of 400-800 ℃ to prepare the flexible electrode material.

Technical Field

The invention relates to the field of electrode materials, in particular to a spinning solution for preparing a carbon fiber material, a flexible electrode material and a preparation method.

Background

In the field of electrode material preparation, the existing carbon fiber material preparation process is realized by sintering organic polymer fibers with extremely high carbon content, the prepared carbon fiber material has low surface polarity and few surface functional groups, is mostly of a solid structure and is mostly represented as a superhard material, and more importantly, the carbon fiber material of the solid structure cannot ensure the complete infiltration of electrolyte, so that the application of the carbon fiber material in an energy storage system is hindered.

At present, in order to realize functionalization of carbon fiber materials, modification of functional groups or secondary loading of other functional active substances on the surface of prepared carbon fiber materials is required. This complicates the practical implementation of carbon fiber materials and renders it impractical to develop more and better in energy storage systems.

Disclosure of Invention

The invention aims to provide at least a spinning solution for preparing a carbon fiber material, a flexible electrode material and a preparation method. The flexible electrode material prepared by the spinning solution has a hollow structure, and can realize excellent mechanical property and excellent electrochemical property.

The invention is realized by the following technical scheme:

first aspect of the invention

A first aspect of the present invention provides a spinning dope for preparing a carbon fiber material, the spinning dope comprising: polyvinylpyrrolidone, a catalyst, tetraethyl silicate, tetrabutyl titanate and an organic solvent. Wherein the catalyst is glacial acetic acid.

In some embodiments, the spinning dope comprises: 5-15 parts of polyvinylpyrrolidone; 5-15 parts of catalyst; tetraethyl silicate, 15-25 parts by weight; 2-8 parts of tetrabutyl titanate; 40-60 parts of organic solvent.

In some embodiments, the spinning dope comprises: 9-11 parts of polyvinylpyrrolidone; 9-11 parts of catalyst; tetraethyl silicate, 18-22 parts by weight; 4-6 parts of tetrabutyl titanate; 50-60 parts of organic solvent.

In some embodiments, the spinning dope further comprises nanomaterials comprising at least one of one-dimensional nanomaterials and two-dimensional nanomaterials; the addition amount of the nano material is 0.1-1 part by weight based on 100 parts by weight of the spinning solution.

In some embodiments, the one-dimensional nanomaterial includes at least one of a carbon nanotube and a metal nanowire; the metal nanowires are VIII, IB and IIIA group metal nanowires. Preferably, the metal nanowires may be gold, silver, copper, nickel, platinum, palladium, aluminum nanowires.

In some embodiments, the two-dimensional nanomaterial includes at least one of graphene oxide, a two-dimensional transition metal carbide, and a two-dimensional transition metal nitride.

In some embodiments, the organic solvent includes at least one of absolute ethanol, N-methylpyrrolidone, dimethylformamide, and dimethylacetamide.

Second aspect of the invention

In a second aspect of the invention there is provided a flexible electrode material prepared from a spinning dope according to the first aspect of the invention.

Since the fiber material prepared by the spinning solution of the first aspect can generate a pore channel structure after spinning, the flexible electrode material of the second aspect is a lithium-philic three-dimensional flexible electrode material with a hollow structure.

Third aspect of the invention

On the basis of the first aspect and the second aspect, the third aspect of the present invention provides a method for preparing a flexible electrode material, including:

adding polyvinylpyrrolidone and glacial acetic acid into an organic solvent, uniformly stirring, and then adding tetraethyl silicate and tetrabutyl titanate to prepare a spinning solution;

carrying out electrostatic spinning on the spinning solution to prepare spinning fibers;

and (3) carrying out activation hydrolysis on the spinning fiber, then introducing inert gas and sintering at the temperature of 400-800 ℃ to prepare the flexible electrode material.

Fourth aspect of the invention

On the basis of the third aspect, the fourth aspect of the present invention provides a preferred preparation method of a flexible electrode material, comprising:

adding polyvinylpyrrolidone, glacial acetic acid and nano materials into an organic solvent, uniformly stirring, and then adding tetraethyl silicate and tetrabutyl titanate to prepare a spinning solution;

carrying out electrostatic spinning on the spinning solution to prepare spinning fibers;

and (3) carrying out activation hydrolysis on the spinning fiber, then introducing inert gas and sintering at the temperature of 400-800 ℃ to prepare the flexible electrode material.

The embodiment of the invention has at least the following beneficial effects:

1. the flexible electrode material prepared in some embodiments of the invention has a hollow structure, can ensure complete infiltration of electrolyte, and has excellent electrochemical performance.

2. According to the flexible electrode material prepared by some embodiments of the invention, the nanometer material is added, and the flexibility of the nanometer material is designed by changing the content of the one-dimensional or two-dimensional nanometer material in the nanometer material, so that the mechanical property of the fiber in the flexible electrode material is improved.

3. The prior art needs to further perform functional group modification or secondary loading of other functional active substances on the surface of the prepared carbon fiber material, but some embodiments of the invention do not have the step, so that the process flow for preparing the flexible electrode material is reduced.

Drawings

FIG. 1 is a schematic cross-sectional view of a carbon fiber material in a flexible electrode material with carbon nanotubes added in example 1;

FIG. 2 is a schematic cross-sectional view of a carbon fiber material in a flexible electrode material of example 8 with graphene oxide added;

FIG. 3 is a schematic cross-sectional view of a carbon fiber material in a flexible electrode material of example 9 with titanium carbide added;

FIG. 4 is a schematic cross-sectional view of the carbon fiber material in the electrode material of comparative example 1 in the prior art;

FIG. 5 is a graph showing the results of electrochemical measurements on the flexible electrode material prepared in example 1;

FIG. 6 is a graph showing the results of electrochemical measurements on the flexible electrode material prepared in example 8;

FIG. 7 is a graph showing the results of electrochemical measurements on the flexible electrode material prepared in example 9;

fig. 8 is a graph showing the results of comparison of electrochemical performance tests of the electrodes prepared in examples 1 and 11.

Detailed Description

The following further describes embodiments of the present invention with reference to the drawings.

First aspect of the invention

A first aspect of the present invention provides a spinning dope for preparing a carbon fiber material, comprising:

polyvinylpyrrolidone, glacial acetic acid, tetraethyl silicate, tetrabutyl titanate and organic solvents.

Wherein the polyvinylpyrrolidone is used for providing a carbon source for the fiber material;

the organic solvent is used to uniformly disperse the component substances, and preferably includes at least one of absolute ethanol, N-methylpyrrolidone, dimethylformamide, and dimethylacetamide. The organic solvent can also be halogenated hydrocarbon solvent, alcohols, amines, nitroalkane, low molecular fatty acid and the like;

the catalyst plays a catalytic role, provides an acidic environment for hydrolysis of tetraethyl silicate and tetrabutyl titanate, and accelerates hydrolysis of tetraethyl silicate and tetrabutyl titanate; the catalyst is preferably glacial acetic acid, and has proper acidity and convenient use amount regulation. Glacial acetic acid can be replaced by acidic substances such as hydrochloric acid, sulfuric acid and the like, but the use amount of the latter two acids needs to be adjusted because the acidity is stronger.

Tetraethyl silicate as SiO₂With tetrabutyl titanate as the TiO source₂The source of (1).

The working principle of the spinning solution is as follows: the raw materials of hydrolyzable tetraethyl silicate and tetrabutyl titanate are added into the spinning solution, and the fiber material produced by spinning the spinning solution can generate a pore channel structure in the fiber through the hydrolysis process of the two substances. Wherein, the generation principle of the pore channel structure is as follows: tetraethyl silicate and tetrabutyl titanate are easy to hydrolyze in water under acidic conditions, and the hydrolysis of the tetraethyl silicate and the tetrabutyl titanate can diffuse from the center of the fiber to the periphery, so that the fiber generates a porous structure. And due to the introduction of the nano flexible material, the overall flexibility of the fiber is further improved.

Therefore, the carbon fiber material prepared by using the spinning solution and the flexible motor prepared by using the carbon fiber material have a hollow structure, and can realize excellent electrochemical performance.

Further, the spinning solution comprises: 5-15 parts of polyvinylpyrrolidone; 5-15 parts of catalyst; tetraethyl silicate, 15-25 parts by weight; 2-8 parts of tetrabutyl titanate; 40-60 parts of organic solvent.

More preferably, the spinning solution comprises: 9-11 parts of polyvinylpyrrolidone; 9-11 parts of catalyst; tetraethyl silicate, 18-22 parts by weight; 4-6 parts of tetrabutyl titanate; 50-60 parts of organic solvent.

The optimal content of each substance of the spinning solution is as follows: 10 parts by weight of polyvinylpyrrolidone; 10 parts by weight of a catalyst; 20 parts by weight of tetraethyl silicate; 5 parts by weight of tetrabutyl titanate; when the organic solvent is 55 parts by weight, the spinning solution fiber has relatively better effect.

Further, the spinning solution further includes a nanomaterial including at least one of a one-dimensional nanomaterial and a two-dimensional nanomaterial.

The nano material has excellent mechanical property, so that the fiber material prepared by the spinning solution has good flexibility, and further preparation of the flexible electrode material is realized. When the spinning solution is prepared, the flexibility of the nano material can be changed by adding different contents of one-dimensional or two-dimensional nano materials or the combination of the one-dimensional or two-dimensional nano materials, so that the mechanical property of the fiber can be improved. Preferably, the spinning solution further comprises a nanomaterial comprising at least one of a one-dimensional nanomaterial and a two-dimensional nanomaterial; the addition amount of the nano material is 0.1-1 part by weight based on 100 parts by weight of the spinning solution. Preferably, the nano material is added in an amount of 0.1-0.5 parts by weight based on 100 parts by weight of the spinning solution, specifically, 0.1-0.5 parts by weight of the nano material is additionally added to 100 parts by weight of the spinning solution.

Preferably, in the spinning solution, the one-dimensional nanomaterial includes at least one of carbon nanotubes and metal nanowires.

The metal nanowires are VIII, IB and IIIA group metal nanowires. Preferably, the metal nanowire is a metal nanowire containing gold, silver, copper, nickel, platinum, palladium and aluminum, so that the prepared carbon fiber material has good mechanical properties.

Preferably, in the spinning solution, the two-dimensional nanomaterial includes at least one of graphene oxide, a two-dimensional transition metal carbide, and a two-dimensional transition metal nitride.

The preferable one-dimensional nano material, two-dimensional nano material and mixture thereof are added, and the mechanical property of the whole prepared spinning fiber can be improved through the flexibility of the one-dimensional or two-dimensional nano material.

Second aspect of the invention

In a second aspect of the invention there is provided a flexible electrode material prepared from a spinning dope according to the first aspect of the invention.

Since the fiber material prepared by the spinning solution of the first aspect can generate a pore channel structure after spinning, the flexible electrode material of the second aspect is a lithium-philic three-dimensional flexible electrode material with a hollow structure.

Third aspect of the invention

On the basis of the first aspect and the second aspect, the third aspect of the present invention provides a method for preparing a flexible electrode material, including:

adding polyvinylpyrrolidone and glacial acetic acid into an organic solvent, uniformly stirring, and then adding tetraethyl silicate and tetrabutyl titanate to prepare a spinning solution;

carrying out electrostatic spinning on the spinning solution to prepare spinning fibers;

and (3) carrying out activation hydrolysis on the spinning fiber, then introducing inert gas and sintering at the temperature of 400-800 ℃ to prepare the flexible electrode material.

In the preparation method, the tetraethyl silicate and the tetrabutyl titanate are easy to hydrolyze in water under an acidic condition, and the hydrolysis of the tetraethyl silicate and the tetrabutyl titanate can diffuse from the center of the fiber to the periphery, so that the fiber has a porous structure. In addition, the protection of the inert gas during sintering can protect the carbon content in the fiber and endow the fiber with electric conductivity.

Fourth aspect of the invention

On the basis of the third aspect, the fourth aspect of the present invention provides a preferred preparation method of a flexible electrode material, comprising: adding polyvinylpyrrolidone, glacial acetic acid and nano materials into an organic solvent, uniformly stirring, and then adding tetraethyl silicate and tetrabutyl titanate to prepare a spinning solution;

the nano material is added into an organic solvent before tetraethyl silicate and tetrabutyl titanate, and if the nano material, the tetraethyl silicate and the tetrabutyl titanate are simultaneously added into the organic solvent, the nano material cannot be uniformly dispersed in the spinning solution, because the tetraethyl silicate and the tetrabutyl titanate are two viscous organic matters, the solvent is viscous after the nano material is added, and the powdery nano material cannot be uniformly dispersed;

carrying out electrostatic spinning on the spinning solution to prepare spinning fibers; electrostatic spinning is a prior art;

and (3) carrying out activation hydrolysis on the spinning fiber, then introducing inert gas and sintering at the temperature of 400-800 ℃ to prepare the flexible electrode material. The textile fiber is placed in the air for more than 24 hours, and the activation hydrolysis can be carried out by water vapor in the air without a catalyst. Adding inert gas such as high-purity argon (with purity of 99.999%) during sintering, mainly protecting the carbon in the fiber from being stable during sintering, and changing the carbon in the air into CO2 gas; the carbon content of the fibers in the prepared flexible electrode material can be protected, and the fibers are endowed with conductivity. The temperature is controlled at 400-800 ℃, which is beneficial to controlling the graphitization degree of carbon and avoiding the graphitization degree of carbon from being too high.

In the preparation method, the tetraethyl silicate and the tetrabutyl titanate are easy to hydrolyze when meeting water under the acidic condition, and the hydrolysis of the tetraethyl silicate and the tetrabutyl titanate can diffuse from the center of the fiber to the periphery, so that the fiber generates a porous structure; and the nano material is added, so that the fiber has better mechanical property. In addition, the protection of the inert gas during sintering can protect the carbon content in the fiber and endow the fiber with electric conductivity.