▎ 摘　　要

NOVELTY - Preparation of graphene sheet comprises: taking graphite, performing heat expansion process, soaking with alkaline solution, filtering, washing and carrying out ultrasonic dispersion in solvent; soaking in inorganic strong protonic acid, filtering, adding hydrogen peroxide solution, washing and drying; carrying out secondary expansion by filtering or drying, carrying out ultrasonic dispersing, filtering and drying. USE - Preparation of graphene sheet.