▎ 摘　　要

NOVELTY - A graphene double-heterojunction preparing method involves selecting a substrate material and growing a 3C-silicon carbide epitaxial layer on the surface of the substrate material. The resultant layer is pyrolyzed for forming a graphene layer to obtain the finished product. USE - Method for preparing a graphene double-heterojunction. ADVANTAGE - The method enables preparing the graphene double-heterojunction with large energy band difference and better lattice match, in a cost effective manner. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a graphene double-heterojunction.