Method for quickly preparing large-size single-crystal graphene

The invention relates to a method for quickly preparing large-size single-crystal graphene on a liquid copper substrate by a chemical vapor deposition process. The method comprises the following steps: in a hydrogen and inert gas atmosphere, introducing vapor and a carbon source, growing large-size single-crystal graphene by using catalytic cracking of the carbon source on the liquid copper substrate surface, and cooling to room temperature in an inert gas atmosphere to obtain the large-size single-crystal graphene. Compared with the traditional solid metal substrate, the liquid copper substrate used in the method has the advantages of high growth speed, uniform nucleation and the like and can be recycled in the aspect of graphene preparation. The carbon source and water content are regulated to implement the controllable graphene size, thereby obtaining the centimeter-sized single-crystal graphene. The prepared graphene is applicable to preparing field-effect transistor devices.