Method for preparing graphene from carbon nanotubes and application of method

The invention relates to the technical field of preparation of graphene and composite materials thereof, in particular to a method for preparing graphene from carbon nanotubes and application of the method. At room temperature, the carbon nanotubes are dispersed in a solvent, and the surfaces of clean metal substrates are coated with dispersion liquid; after the solvent is volatilized, the carbon nanotubes are clamped between the metal substrates for rolling under the condition of no lubrication at room temperature; after rolling for one time, a sample is folded in half, continuously rolling is carried out, repeatedly folding in half is carried out, and rolling is carried out to a certain pass; and after rolling is completed, the carbon nanotubes are gradually unfolded to generate the graphene. The preparation method does not need chemical reagents, is simple in process, free of chemical pollution and high in efficiency, can obtain high-quality graphene with low layer number, and is suitable for industrial pr