▎ 摘　　要

NOVELTY - Producing graphene, comprises (a) adding graphite into mixture of sulfuric acid and nitric acid, and primary stirring the mixture to penetrate between the layers of the graphite to obtain mixture, (b) adding oxidizing agent into the mixture, and mixing the surface of the graphite to oxidize by stirring, (c) recovering the graphite from the mixture, and primary expanding the graphite by adding a separate reaction solution, (d) performing e.g. plasma process on the graphite, and secondarily expanding the graphite, and (e) dispersing and expelling the expanded graphite to obtain a graphene flake. USE - The method is useful for producing graphene (claimed). ADVANTAGE - The method produces high quality graphene. DETAILED DESCRIPTION - Producing graphene, comprises (a) adding graphite into mixture of sulfuric acid and nitric acid, and primary stirring the mixture to penetrate between the layers of the graphite to obtain mixture, (b) adding oxidizing agent into the mixture, and mixing the surface of the graphite to oxidize by stirring, (c) recovering the graphite from the mixture, and primary expanding the graphite by adding a separate reaction solution, (d) performing plasma process, microwave process or a rapid thermal annealing process on the graphite, and secondarily expanding the graphite, and (e) dispersing and expelling the expanded graphite to obtain a graphene flake.