CN-122025681-A - Composite electrode material, preparation method thereof and flow battery

CN122025681ACN 122025681 ACN122025681 ACN 122025681ACN-122025681-A

Abstract

The application belongs to the field of flow batteries, and particularly relates to a composite electrode material, a preparation method thereof and a flow battery. The application discloses a composite electrode material which comprises a carbon-based electrode matrix, and a metal oxide formed on the carbon-based electrode matrix, wherein the metal oxide is connected with the carbon-based electrode matrix through an M-O-C bond, and M is metal in the metal oxide. The composite electrode material prepared by the application contains M-O-C bonds, so that the catalytic activity of the carbon-based electrode matrix can be improved and the polarization of the flow battery can be reduced.

Inventors

LIU BO
WANG LECHENG
WANG ZHIBO
QIN YU
Jiang Jiacen

Assignees

沈阳恒久安泰环保与节能科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. A composite electrode material, comprising: a carbon-based electrode matrix; a metal oxide formed on the carbon-based electrode substrate, the metal oxide being connected to the carbon-based electrode substrate by an M-O-C bond; Wherein M is a metal in the metal oxide.
2. The composite electrode material according to claim 1, wherein, The carbon-based electrode matrix is at least one of graphite felt, carbon paper or carbon cloth; the metal includes at least one of manganese, zinc, iron, bismuth, nickel, copper, vanadium, and titanium.
3. A flow battery, comprising: A composite electrode material according to any one of claims 1 to 2.
4. A method of producing a composite electrode material, characterized in that the method of producing a composite electrode material is used for producing the composite electrode material according to any one of claims 1 to 2, the method comprising: pretreating the carbon-based electrode matrix to increase the hydrophilicity of the carbon-based electrode matrix; immersing the pretreated carbon-based electrode substrate into a metal salt solution for mixing, so that metal salt in the metal salt solution is attached to the carbon-based electrode substrate to form a metal precursor layer; And carrying out heat treatment in a first temperature range on the carbon-based electrode matrix formed with the metal precursor in an inert gas environment to decompose the metal precursor into metal oxide, and carrying out carbothermal reduction reaction with the carbon-based electrode matrix for a first preset time period to obtain the composite electrode material with M-O-C bonds.
5. The method of preparing a composite electrode material according to claim 4, wherein the pretreating the carbon-based electrode substrate comprises: Heating the carbon-based electrode matrix to a temperature in the range of 100-400 ℃ at a heating rate of 1-10 ℃ per minute; Under the air-gas environment, the carbon-based electrode matrix is oxidized for 2-6 h at a constant temperature within the range of 100-400 ℃; and cooling the oxidized carbon-based electrode matrix to room temperature at a cooling rate of 3-5 ℃ per minute.
6. The method of producing a composite electrode material according to claim 5, wherein the pretreatment process further comprises, before the heating of the carbon-based electrode substrate to a temperature in the range of 100 ℃ to 400 ℃ at a heating rate of 1 ℃ to 10 ℃ per minute: Soaking the carbon-based electrode matrix in a solvent to clean for 0.5-1 h so as to remove impurities of the carbon-based electrode matrix and obtain the cleaned carbon-based electrode matrix; wherein the solvent is at least one of ethanol, acetone and deionized water.
7. The method for producing a composite electrode material according to claim 4, wherein, The metal salt is at least one of nitrate, acetate or sulfate.
8. The method for producing a composite electrode material according to claim 4, wherein, The percentage concentration of the metal salt solution is 0.1% -30%.
9. The method for producing a composite electrode material according to claim 4, wherein, The metal salt is used in an amount of 1 part to 50 parts with respect to 100 parts by weight of the carbon-based electrode substrate.
10. The method for producing a composite electrode material according to claim 4, wherein, The inert gas is at least one of nitrogen, argon or a mixed gas thereof; The first temperature range is 400-800 ℃; the first preset time length is 1h-5h.

Description

Composite electrode material, preparation method thereof and flow battery Technical Field The application relates to the field of flow batteries, in particular to a composite electrode material, a preparation method thereof and a flow battery. Background The carbon-based electrode matrix of the flow battery serves as a place where electrochemical reactions occur, and the performance of the carbon-based electrode matrix determines the power density and long-term cycling stability of the flow battery. However, currently commercial carbon-based electrode matrices have low catalytic activity, resulting in greater polarization of flow batteries. In order to increase the catalytic activity of the carbon-based electrode matrix and thereby reduce the polarization of flow batteries, various techniques have been disclosed. One is to increase the specific surface area and oxygen-containing functional groups of the carbon-based electrode matrix to improve the catalytic activity of the carbon-based electrode matrix, but the specific surface area and the oxygen-containing functional groups are limited in increase, so that the high-power operation requirement of the flow battery cannot be met. And secondly, doping hetero atoms on the surface of the carbon-based electrode matrix, wherein the difference of the optimizing effect of the doped hetero atoms on the specific flow battery is larger, the promotion of the catalytic activity is limited, and the preparation process of doping the hetero atoms on the surface of the carbon-based electrode matrix is more complex. Thirdly, the flow electrode is subjected to heat treatment and metal oxide is loaded, but the metal oxide is mainly fixed on the surface of the carbon-based electrode matrix by virtue of Van der Waals force, and the metal oxide is in point contact with the carbon-based electrode matrix, so that higher contact resistance exists, and the flow battery is not beneficial to running under high current density. In addition, in the long-term operation process of the flow battery, the strongly acidic electrolyte is easy to cause the metal oxide to fall off from the surface of the carbon-based electrode matrix, so that the electrolyte is polluted, and further the performance of the flow battery is continuously reduced and the cycle life is shortened. Disclosure of Invention The application provides a composite electrode material, a preparation method thereof and a flow battery, wherein an M-O-C bond is constructed between a carbon-based electrode matrix and a metal oxide through carbothermic reaction. The M-O-C bond forms stable connection by virtue of electrons among atoms, the bond energy is far higher than Van der Waals force, the contact resistance of the surface of the carbon-based electrode matrix can be reduced, and the anti-falling capability of the metal oxide in the strong acid electrolyte can be improved, so that the problems of low catalytic activity of the carbon-based electrode matrix and large polarization of the flow battery are solved. In a first aspect, an embodiment of the present application provides a composite electrode material, including a carbon-based electrode substrate, and a metal oxide formed on the carbon-based electrode substrate, where the metal oxide is connected to the carbon-based electrode substrate through an m—o—c bond, and M is a metal in the metal oxide. In one possible implementation, the carbon-based electrode matrix is at least one of graphite felt, carbon paper or carbon cloth, and the metal comprises at least one of manganese, zinc, iron, bismuth, nickel, copper, vanadium and titanium. In a second aspect, the embodiment of the application also provides a flow battery, which comprises the composite electrode material provided in the first aspect of the application. In a third aspect, an embodiment of the present application provides a method for preparing a composite electrode material, where the method is used for preparing the composite electrode material provided in the first aspect of the present application, and the method includes pretreating the carbon-based electrode substrate to increase hydrophilicity of the carbon-based electrode substrate, immersing the pretreated carbon-based electrode substrate in a metal salt solution, mixing the metal salt in the metal salt solution to adhere to the carbon-based electrode substrate to form a metal precursor layer, and performing a heat treatment in an inert gas environment at a first temperature range on the carbon-based electrode substrate with the metal precursor formed therein to decompose the metal precursor into a metal oxide, and performing a carbothermic reaction with the carbon-based electrode substrate for a first preset period of time to obtain a composite electrode material having an M-O-C bond. In one possible implementation, the pretreatment of the carbon-based electrode matrix comprises heating the carbon-based electrode matrix to a temperature ranging from 100 ℃ to