▎ 摘　　要

NOVELTY - The preparation method of graphene involves (i) taking a mixture of graphite powder and graphene as raw material, adding raw materials into a reaction kettle, adding leaching solution, and extracting to obtain a suspension, separating and filtering the suspension to obtain an enriched graphene solution, (ii) distilling the graphene solution under reduced pressure, increasing the concentration of graphene oxide solution, reducing the graphene oxide solution to obtain graphene precipitate, drying the graphene, and precipitating and calcining the graphene. USE - Preparation of graphene (claimed). ADVANTAGE - The environmentally-friendly method enables the preparation of graphene rapidly with high efficiency, without the addition of strong acid, and without producing strong acid residues, and metal ion residue.