▎ 摘　　要

NOVELTY - Natural flaky graphite is dispersed in mixed solution of ethanol and concentrated nitric acid in volume ratio of 50:1-50:10, to obtain 0.005-0.05 g/mL suspension. The suspension is hydrothermally reacted at 80-160 degrees C for 6-48 hours, cooled, filtered, precipitated, washed and dried, to obtain expandable graphite. The expandable graphite is added to organic foaming agent solution and allowed to standstill for 30 minutes to 3 hours, stirred at room temperature for 1-5 hours, ultrasonically treated for 13-60 minutes, cooled and dried in vacuum, to obtain graphene. USE - Preparation of graphene (claimed). ADVANTAGE - The method efficiently and economically provides graphene without adding stabilizer.