Preparation method of graphene thin film

Abstract

The invention discloses a preparation method of a graphene thin film. The preparation method comprises the following steps: 1, adding graphene oxide into a mixed solvent and dissolving to obtain a precursor solution; 2, adding metal into the precursor solution and carrying out photocatalytic weak reduction reaction; after standing, layering to obtain weakly-reduced graphene colloid; 3, coating a substrate with the weakly-reduced graphene colloid to obtain a weakly-reduced graphene thin film attached on the surface of the substrate; 4, reducing the weakly-reduced graphene thin film attached onthe surface of the substrate and drying to obtain the graphene thin film. According to the preparation method disclosed by the invention, graphite oxide is weakly photocatalytically reduced into weakly-reduced graphene and then the weakly-reduced graphene is reduced into the graphene thin film; part of oxygen-containing groups are also remained on the weakly-reduced graphene, so that the graphenethin film has a self-assembling capability and the orderliness of the weakly-reduced graphene colloid is ensured; the quality of the graphene thin film is improved, the shrinkage and agglomeration ofthe graphene thin film in a drying process are reduced, damages to the graphene thin film are avoided and a size range of the graphene thin film is expanded.

Description

technical field [0001] The invention belongs to the technical field of graphene material preparation, in particular to a method for preparing a graphene film. Background technique [0002] Graphene is a hexagonal close-packed two-dimensional crystal composed of a single layer of carbon atoms. It has the advantages of high electrical conductivity, high light transmittance, excellent mechanical strength and chemical stability. Therefore, graphene two-dimensional assembled film is widely used in the field of electronic devices. , nanofiltration membrane and other fields have broad application prospects. [0003] At present, researchers can use a variety of methods to prepare high-quality graphene, such as mechanical exfoliation, redox, chemical vapor deposition, crystal epitaxial growth, etc., and then use suction filtration, spin coating, spray coating , LB film method, etc. to prepare graphene into graphene paper or film. In the preparation process of the above-mentioned gr...

AI Technical Summary

Problems solved by technology

In the preparation process of the above-mentioned graphene film, graphene oxide is mostly used as raw material, but during the solvent volatilization process of the preparation process, the graphene oxide film is easy to shrink and agglomerate, resulting in incomplete surface of the film. If graphene is directly used as raw material , not only requires high uniformity of graphene size, but also graphene basically has no self-assembly ability in the preparation process

The most commonly used redox method uses graphite as raw material, which has the advantages of simple process, low cost, and large-scale production. However, the graphene oxide and graphene powder obtained by this method are small in size and easy to agglomerate, which is not easy application, it is not possible to further prepare large-scale graphene assemblies to regulate the properties of graphene and expand the application range of graphene