阅读说明：本技术 一种导电聚合物基超级电容器电极及其制备方法 (Conductive polymer-based supercapacitor electrode and preparation method thereof ) 是由 刘文娜 叶羽敏 王宏 何祥聪 于 2021-07-06 设计创作，主要内容包括：本发明公开一种超级电容器电极材料及其制备方法。本发明所述材料通过在具有纳米结构的基底上氧化化学气相沉积导电聚合物获得；所述氧化化学气相沉积是通过将气化的单体和氧化剂通入反应器,在温度可控的基底上反应生成厚度可控、保形性好的导电聚合物膜层。本发明方法制备得到的超级电容器电极材料,不仅提高了聚合物基超级电容器的比电容,同时保持了电极材料良好的循环寿命。(The invention discloses a super capacitor electrode material and a preparation method thereof. The material of the invention is obtained by oxidizing a chemical vapor deposition conductive polymer on a substrate with a nano structure; the oxidative chemical vapor deposition is to introduce gasified monomers and oxidant into a reactor to react on a substrate with controllable temperature to generate a conductive polymer film layer with controllable thickness and good shape retention. The supercapacitor electrode material prepared by the method not only improves the specific capacitance of the polymer-based supercapacitor, but also keeps the good cycle life of the electrode material.)

1. A supercapacitor electrode material, characterized in that: the supercapacitor electrode material comprises a conductive polymer and a substrate material with a nano structure, and is obtained by oxidizing a chemical vapor deposition conductive polymer on a substrate with the nano structure;

the conductive polymer is one or more of poly (3, 4-ethylenedioxythiophene), polyaniline and poly (3-methylthiophene);

the substrate material with the nano structure is any one of SiC nanowires, nanobelts, nanorods and carbon fiber cloth on which SiC nanomaterials grow.

2. A preparation method of a super capacitor electrode material is characterized by comprising the following steps: depositing a layer of conductive polymer on the surface of a substrate material with a nano structure by using a chemical vapor deposition method, wherein the reaction is completed in a reactor for oxidizing chemical vapor deposition, and the method comprises the following steps:

fixing a base material to be deposited on a reactor sample table, and controlling the base material to be deposited at 25-200 ℃;

placing oxidant powder into a crucible below the reactor, covering a baffle plate in a screwing manner, and controlling the temperature of the crucible to be 150-250 ℃;

vacuumizing the reactor, wherein the vacuum degree is 200-900 mTorr, and unscrewing a baffle above the crucible after the set vacuum degree is reached;

and step four, introducing the gasified conductive polymer monomer into a reactor, reacting under the action of a gaseous oxidant, and covering a conductive polymer film layer on the surface of the substrate to prepare the electrode material of the supercapacitor.

3. The preparation method of the electrode material of the supercapacitor as claimed in claim 2, wherein: the rotation frequency of a sample stage in the oxidation chemical vapor deposition reactor is 0-100 rad/min; the temperature of the sample stage is 25-200 ℃.

4. The preparation method of the electrode material of the supercapacitor as claimed in claim 2, wherein: the conductive polymer is prepared by the polymerization reaction of the following monomers; the monomer is one or the combination of more than two of 3, 4-ethylenedioxythiophene, thiophene, aniline and 3-methylthiophene.

5. The method for preparing the electrode material of the supercapacitor as claimed in claim 2 or 4, wherein: and finally obtaining the conductive polymer film layer with the composition gradient through monomer flow control.

6. The preparation method of the electrode material of the supercapacitor as claimed in claim 2, wherein: the oxidant is one or the combination of more than two of ferric trichloride, vanadium oxychloride and antimony pentachloride.

7. The preparation method of the electrode material of the supercapacitor as claimed in claim 6, wherein: the ratio of the monomer to the oxidant is 1: 10-1: 30.

8. The preparation method of the electrode material of the supercapacitor as claimed in claim 7, wherein: the sample obtained after the oxidation chemical vapor deposition method can be subjected to one or more of hydrobromic acid, sulfuric acid, hydrochloric acid and methanol soaking treatment in sequence according to needs, and then is subjected to vacuum drying.

9. The preparation method of the electrode material of the supercapacitor as claimed in claim 8, wherein: the conductive polymer is Cl^-Doping the conductive polymer.

Technical Field

The invention relates to the field of super capacitors, in particular to a conducting polymer-based super capacitor electrode and a preparation method thereof.

Background

The increasing development of intelligent electronic products has stimulated a great demand for safe and reliable energy storage devices. Among the many energy storage devices, supercapacitors have been extensively studied for their higher power and energy density. Conductive polymers have attracted considerable attention in energy storage applications due to their advantages of good conductivity, flexibility, processability, and low cost. However, redox reactions in electrochemical energy storage processes can cause volume changes of conductive polymers, thereby causing poor cycle stability, which is an important factor limiting practical applications. The conductive polymer is coated on other stable substrate materials with nano structures to construct the composite electrode, so that the stability of the composite electrode can be improved, the specific surface area of the composite electrode can be enlarged, the active sites can be increased, and the charge transfer distance can be shortened. However, conventional solution coating methods, such as spin coating, dip coating, or electrochemical deposition, are selective for the substrate material, the resulting thin film is poorly conductive, and it is difficult to retain the nanostructure of the substrate, which may block the nanocavities inside the substrate material, thereby reducing the number of active sites. Therefore, the search for a gas phase process to prepare highly conductive, highly conformal conductive polymers is critical to facilitate their use in energy storage.

Disclosure of Invention

The invention aims to provide a conducting polymer-based supercapacitor electrode; the invention also aims to provide a preparation method of the conducting polymer-based supercapacitor electrode; the method provides a method for conformally depositing a high-conductivity polymer on the surface of a substrate with a nano structure by utilizing a chemical vapor deposition technology, and simultaneously provides a stable and efficient electrode material of a super capacitor.

In order to achieve the above object, the present invention provides a supercapacitor electrode material comprising a conductive polymer and a substrate material having a nanostructure;

the conductive polymer is one or more of poly (3, 4-ethylenedioxythiophene), polyaniline and poly (3-methylthiophene);

the substrate material with the nano structure is any one of SiC nanowires, nanobelts, nanorods and carbon fiber cloth with the SiC material.

The preparation method of the supercapacitor electrode material adopts a chemical vapor deposition method to deposit a layer of conductive polymer on the surface of a substrate with a nano structure, and the reaction is completed in a reactor for oxidizing chemical vapor deposition, and comprises the following steps:

fixing a base material to be deposited on a sample table above a reactor, and controlling the base material at 25-200 ℃;

placing an oxidant into a crucible below the reactor, covering a baffle plate in a screwing manner, and controlling the temperature of the crucible to be 150-250 ℃;

pumping a preset vacuum degree in the reactor, wherein the vacuum degree is 200-900 mTorr, and unscrewing a baffle above the crucible;

and step four, introducing the gasified conductive polymer monomer into a reactor, reacting under the action of oxidant gas, and covering the surface of the substrate with a conductive polymer film layer to obtain the electrode material of the supercapacitor.

The rotation frequency of a sample stage in the oxidation chemical vapor deposition reactor is 0-100 rad/min; the temperature of the sample stage is 25-200 ℃.

The conductive polymer is prepared by the polymerization reaction of the following monomers; the monomer is one or the combination of more than two of 3, 4-ethylenedioxythiophene, thiophene, aniline and 3-methylthiophene.

And finally obtaining the conductive polymer film layer with the composition gradient through monomer flow control.

The oxidant is one or the combination of more than two of ferric trichloride, vanadium oxychloride and antimony pentachloride.

The ratio of the monomer to the oxidant is 1: 10-1: 30.

The sample obtained after the oxidation chemical vapor deposition can be subjected to one or more of hydrobromic acid, sulfuric acid, hydrochloric acid and methanol soaking treatment in sequence according to needs, and then vacuum drying is carried out.

The conductive polymer is Cl^-Doping the conductive polymer.

The conductive polymer-based supercapacitor electrode and the preparation method thereof have the beneficial effects that: the method has no special requirements on the substrate, no solvent residue, uniform film, good shape retention and high conductivity; aiming at the defect that the specific capacitance of the conventional conductive polymer used for the electrode material of the super capacitor is lower, the conductive polymer is deposited on the substrate material with the nano structure and used as the self-supporting electrode material of the super capacitor, so that the specific capacitance of the super capacitor is improved, and the cycling stability of the electrode material is kept.

Drawings

FIG. 1 is a schematic view of an oxidative chemical vapor deposition coating apparatus according to the present invention;

FIG. 2 is a scanning electron microscope image of PEDOT-coated SiC nanorods prepared in examples 1-4, respectively;

FIG. 3 is a transmission electron microscope image of PEDOT-coated SiC nanorods prepared in example 3;

fig. 4(a) is a cyclic voltammogram of the PEDOT-coated SiC nanowire composite electrode and the pure SiC nanowire electrode prepared in examples 1 to 4;

FIG. 4(b) is a graph showing the change of specific capacitance with sweeping speed of the PEDOT-coated SiC nanowire composite electrode and the pure SiC nanowire electrode prepared in examples 1 to 4;

FIG. 5 shows the construction of an electrode in example 3 with a sweep rate of 10 to 200mV s under a two-electrode system^-1Cyclic voltammetry of (a);

fig. 6 is a graph showing the cycle stability of the electrode constructed in example 3 measured by a constant current charge and discharge method under a two-electrode system.

Detailed Description

Example 1

The invention relates to a preparation method of a conducting polymer-based supercapacitor electrode, which is prepared by the following steps:

fixing the carbon fiber cloth with the SiC nano-rods on a sample table above an oxidation chemical vapor deposition reactor, and controlling the temperature of the sample table at 100 ℃; ferric trichloride is taken as an oxidant, and the temperature of the oxidant is controlled at 230 ℃; pumping the mixture to 300mTorr, introducing 3, 4-ethylene dioxythiophene monomer with the flow of 3sccm, depositing for 5min, stopping the reaction, and naturally cooling.

Example 2

The invention relates to a preparation method of a conducting polymer-based supercapacitor electrode, which is prepared by the following steps:

fixing the carbon fiber cloth with the SiC nano-rods on a sample table above an oxidation chemical vapor deposition reactor, and controlling the temperature of the sample table at 100 ℃; ferric chloride is used as an oxidant, and the temperature of the oxidant is controlled at 230 ℃; pumping the mixture to 300mTorr in vacuum, introducing 3, 4-ethylene dioxythiophene monomer with the flow rate of 3sccm, depositing for 10min, stopping the reaction, and naturally cooling.

Example 3

The invention relates to a preparation method of a conducting polymer-based supercapacitor electrode, which is prepared by the following steps:

fixing the carbon fiber cloth with the SiC nano-rods on a sample table above an oxidation chemical vapor deposition reactor, and controlling the temperature of the sample table at 100 ℃; ferric chloride is used as an oxidant, and the temperature of the oxidant is controlled at 230 ℃; pumping the mixture to 300mTorr in vacuum, introducing 3, 4-ethylene dioxythiophene monomer with the flow rate of 3sccm, depositing for 15min, stopping the reaction, and naturally cooling.

Example 4

The invention relates to a preparation method of a conducting polymer-based supercapacitor electrode, which is prepared by the following steps:

fixing the carbon fiber cloth with the SiC nano-rods on a sample table above an oxidation chemical vapor deposition reactor, and controlling the temperature of the sample table at 100 ℃; ferric chloride is used as an oxidant, and the temperature of the oxidant is controlled at 230 ℃; pumping the mixture to 300mTorr in vacuum, introducing 3, 4-ethylene dioxythiophene monomer with the flow rate of 3sccm, depositing for 20min, stopping the reaction, and naturally cooling.

In summary, examples 1-4 show that:

depositing a PEDOT film on the surface of the SiC fiber by using an oxidation chemical vapor deposition method, wherein the obtained film layer is uniform and has good shape retention (figures 2 and 3);

the approximate rectangular cyclic voltammetry curve proves that the electrode material has good conductivity and small internal resistance (figure 4 a);

the energy storage characteristics of the SiC fibers can be obviously improved by depositing the PEDOT coating through comparing the specific capacitance, and the optimal specific capacitance is obtained by regulating and controlling the morphology of the coating (figure 4 b);

an optimized SiC @ PEDOT-15 electrode is selected for constructing the super capacitor, and a two-electrode system is adopted for representing the energy storage characteristic of the super capacitor, so that the result shows that the super capacitor has great potential in the aspect of energy storage of the super capacitor (figure 5);

the cycle stability of the obtained device was measured, and it was found that the energy storage characteristics thereof remained 104% of the initial value after 10000 cycles, exhibiting excellent cycle stability (fig. 6).

The conductive polymer can be one or more of poly (3, 4-ethylenedioxythiophene), polyaniline and poly (3-methylthiophene), but is not limited to the poly (3, 4-ethylenedioxythiophene);

the substrate material having the nanostructure may be, but is not limited to, any one of SiC nanowires, nanobelts, nanorods, and carbon fiber cloth on which SiC nanomaterial is grown.

The conductive polymer is prepared by the polymerization reaction of the following monomers; the monomer can be one or the combination of more than two of 3, 4-ethylene dioxythiophene, thiophene, aniline and 3-methyl thiophene.

The oxidant can be one or the combination of any two or more of ferric trichloride, vanadium oxychloride and antimony pentachloride.