▎ 摘　　要

NOVELTY - A supercritical device comprises reaction device (1), heating device (2) and oxidant adding device (3). The heating device is connected with reaction device for heating. The oxidant adding device is connected with reaction device for adding oxidant. USE - Supercritical device used for preparing graphene (claimed). ADVANTAGE - The device has low cost, releases heat, ensures quality, increases graphene yield and interlayer distance of carbon material, makes organic solvent and carbonaceous raw material physical reaction, and generates oxidation reaction on oxidant and organic solvent. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for use method of supercritical device. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of supercritical device. Reaction device (1) Heating device (2) Oxidant adding device (3)