▎ 摘　　要

NOVELTY - Preparation of graphene nanofilms involves immersing a cathode and an anode comprising a graphite foil, in a persulfate electrolyte aqueous solution, applying a positive voltage to the anode and applying a negative voltage to the cathode to peel off the graphene nanofilms from the anode, and separating the graphene nanofilms from the electrolyte. The graphene nanofilms are peeled by performing local oxygen functionalization, such that several gas components are formed by joining an oxygen functional group locally between the edges of the laminated graphite layers. USE - Preparation of graphene nanofilms used in preparation of nano ink (claimed). DETAILED DESCRIPTION - Preparation of graphene nanofilms involves immersing a cathode and an anode comprising a graphite foil, in a persulfate electrolyte aqueous solution, applying a positive voltage to the anode and applying a negative voltage to the cathode to peel off the graphene nanofilms from the graphite layer of the anode, and separating the graphene nanofilms from the electrolyte. The graphene nanofilms are peeled by performing local oxygen functionalization, such that several gas components are formed by joining an oxygen functional group locally between the edges of the laminated graphite layers. During the local oxygen functionalization, hydroxide and oxygen ions are generated at the edges of the graphite layer when water in the aqueous electrolyte solution is electrolyzed, and persulfate ions promote peeling of graphite layer. An INDEPENDENT CLAIM is included for preparation of nano ink, which involves ultrasonically dispersing graphene nanofilms in an organic solvent.