▎ 摘　　要

NOVELTY - Preparation of graphene involves forming a carbon layer on a flame-coated substrate which has catalytic function or flame-coated substrate which does not have catalytic function using carbon source. USE - Preparation of graphene used for preparing doped graphene (claimed). ADVANTAGE - The method efficiently and economically provides high-quality graphene having high crystallizing degree, by simple process under controlled reaction conditions. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) preparation of doped graphene, which involves cooling graphene using aqueous solution containing metal ions as cooling agent; and (2) graphene.