▎ 摘　　要

NOVELTY - Preparing supercritical fluid graphene comprises e.g. placing graphite in solution mixture containing oxidant and intercalating agent, stirring at 20-60 degrees C for 0.5-5 hours, washing obtained product, filtering, drying in muffle furnace, carrying out high temperature treatment at 600-1200 degrees C for 3-60 seconds under air atmosphere to obtain expanded graphite product, adding into polytetrafluoroethylene container, sealing, placing in high pressure kettle, sealing upper cover and injecting supercritical fluid, adjusting temperature at 40-160 degrees C and pressure at 5-30 MPa. USE - The method is useful for preparing supercritical fluid graphene (claimed). ADVANTAGE - The method is simple, economical and suitable for industrial production. The graphene has low impurity content, lower stratum and thin thickness. DETAILED DESCRIPTION - Preparing supercritical fluid graphene comprises (i) placing graphite in solution mixture containing oxidant and intercalating agent, stirring at 20-60 degrees C for 0.5-5 hours, washing obtained product, filtering, drying in muffle furnace, carrying out high temperature treatment at 600-1200 degrees C for 3-60 seconds under air atmosphere to obtain expanded graphite product, (ii) adding step (i) product into polytetrafluoroethylene container, sealing, placing in high pressure kettle, sealing upper cover, injecting supercritical fluid, adjusting temperature at 40-160 degrees C and pressure at 5-30 MPa, so that one of the supercritical fluid in a supercritical state, reacting under magnetic force stirring for 1-24 hours, releasing air through valve, taking out reaction product, adding certain amount of dispersing solvent, dispersing through ultrasonic and stirring process, centrifuging the product to obtain supernatant graphene.