▎ 摘　　要

NOVELTY - Preparation of self-supporting flexible graphene film involves (1) preparing graphene nanosheets with surface oxidation and internal crystallization by regulating and controlling voltage and distance between two graphite electrodes, where an electrolyte is 1 M ammonium sulfate, and the voltage value is ±10 V, placing the two pretreated electrodes oppositely in the electrolyte, where the distance between the electrodes is 3-30 cm, (2) preparing 10-30 mg/mL graphene slurry having a viscosity of 20-30 mPa.seconds by using the prepared graphene nanosheets and deionized water as a solvent, and performing scraper coating and evaporation self-assembly on the surface of a substrate to prepare a self-supporting graphene film, and (3) patterning the graphene film into a self-supporting flexible graphene film in any shape by using a laser engraving machine. USE - Preparation of graphene film used in self-supporting flexible supercapacitor electrode (claimed) of energy storage device e.g. battery. ADVANTAGE - The surface oxidized and inner part crystal of the graphene is easy to process, taking water as solvent to prepare slurry without need of agglomerant, conductive agent. When assembling the flexible self-supporting plane micro super capacitor, without substrate and current collector, which is good for the actual application of the super capacitor.