Preparation method of high quality graphene conductive film

Abstract

The invention belongs to the technical field of graphene materials and relates to a preparation method of a high quality graphene conductive film. The preparation method comprises the following steps: uniformly mixing natural flake graphite with mixed acid in a reactor, then adding an intercalator and stirring to react, and filtering, washing and drying to obtain layered graphite; then after microwave treatment of the layered graphite, dispersing the layered graphite in water for ultrasonic exfoliation to form a graphene aqueous liquid, and dispersing the centrifugalized graphene aqueous liquid in a solvent to obtain a graphene dispersion liquid; and then after ultrasonic treatment of the graphene dispersion liquid, forming a graphene thin film by virtue of dispensing or filtration of a cellulose filter membrane and polishing the surface of the graphene thin film, and furthermore, transferring the substrate and heating the graphene thin film to prepare the graphene conductive film. The preparation method is simple and convenient to operate, the controllability of process parameters is high and the production cost is low, and moreover, strong oxidants and toxic reducers are avoided, and the preparation method is environment-friendly.

Description

Technical field: [0001] The invention belongs to the technical field of graphene material preparation and relates to a method for preparing a high-quality graphene conductive film. Background technique: [0002] Graphene is a carbon atom with sp 2 The hybridized orbitals form a hexagonal planar film with a honeycomb lattice, a two-dimensional material with a thickness of only one carbon atom. In 2004, scientists at the University of Manchester in the United Kingdom stripped graphene for the first time and confirmed that it can exist stably. Since then, graphene, a new type of material, has received widespread attention. Graphene has very excellent properties, and its specific surface area is as high as 2630m 2 .g -1 , sign mobility up to 200000cm 2 .v -1 .s -1 , Young's modulus up to 1.0TPa, thermal conductivity constant of 5000W.m -1 .K -1 , the optical transmittance is as high as 97.7%, and its conductivity is also very good, almost reaching the conductivity of a s...

AI Technical Summary

Problems solved by technology

[0003] At present, the preparation methods of graphene mainly include mechanical exfoliation method, chemical vapor deposition method, epitaxial growth method, solvent exfoliation method and chemical redox method. It is not suitable for large-scale industrial production of graphene; chemical vapor deposition and epitaxial growth methods have disadvantages such as complex process, harsh conditions, low yield, and high cost, which limit their large-scale industrial production and application of graphene; epitaxial growth The method is used to grow graphene by heating SiC epitaxy for electronic devices, etc., but because the SiC crystal surface is prone to reconstruction during the heating process, it is difficult to obtain large-area uniform graphene, and the heating temperature is high and energy consumption is large; the solvent stripping method The stripping efficiency and yield are low, and there are few applicable solvents; the chemical redox method is currently a low-cost, large-scale method for preparing graphene, but the strong oxidizing agent used in the stripping process of the chemical stripping method will destroy the graphene carbon. The planar structure of atoms produces defects, which lead to a decrease in the conductivity of graphene, and toxic chemicals such as hydrazine hydrate, which are usually used in the reduction process, are likely to pollute the environment

However, the graphene film prepared by redox method has low electrical conductivity, many defects, and poor mechanical properties; and the solvent dispersibility and film-forming property of graphite bulk material are poor; Good stability and film-forming properties, but poor conductivity and high resistance

Images