▎ 摘　　要

NOVELTY - Natural graphite powder and acid are added into a container, stirred, filtered, excess acid is removed, additive is added to the resultant product, and stirred. The resultant mixed material is transferred to a low-temperature container, and cooled, to obtain low-temperature graphite slurry. The obtained graphite slurry is quickly injected into a reactor filled with supercritical fluid medium, temperature and pressure of material in the reactor are controlled, processed, filtered, separated, and dried, to obtain graphene product. USE - Preparation of graphene (claimed). ADVANTAGE - The method enables preparation of graphene having excellent electrical and thermal properties with improved yield by approximately 2-5 times.