Preparation method of graphene and graphene prepared by same

The invention relates to a preparation method of graphene and graphene prepared by the method, and is characterized in that the method adopts graphite as a raw material; a graphite intercalation compound is prepared by intercalating metal between graphite layers; and then graphene is prepared by peeling the graphite intercalation compound. The graphene prepared by the method has a length and a width of 5-15000 nm, and a thickness of 0.3-15 nm. The advantages of the invention are that: the raw material source is wide; the cost is low; the preparation method is simple; the product performance is stable and controllable; and the method is suitable for industrial production.