▎ 摘　　要

NOVELTY - Preparing graphene comprises adding ion liquid in solvent and carrying out ultrasonic dispersion, and forming ion liquid solution, adding the expanded graphite into the ion liquid solution, carrying out ultrasonic dispersion to obtain suspension, adding agate ball into the suspension, adding agate ball in ball milling pot and ball milling to obtain micro sheet graphene solution, adding the obtained micro sheet graphene solution into a reactor and sealing, carrying out heat treatment and removing the pressure of the reactor to obtain the graphene. USE - The method is useful for preparing graphene (claimed). ADVANTAGE - The method assures instantaneous release of fluid pressure, which destroys the Van der Waals force between the graphite layers, thus obtaining high rate monolayer graphene and dispersing it evenly to obtain graphene. DETAILED DESCRIPTION - Preparing graphene comprises adding ion liquid in solvent and carrying out ultrasonic dispersion, and forming ion liquid solution, where the mass ratio of ion liquid and solvent is 1:1-1:5, adding the expanded graphite into the ion liquid solution, carrying out ultrasonic dispersion to obtain suspension, adding agate ball into the suspension, where the mass ratio of agate ball and the suspension is 15:1-20:1, adding agate ball in ball milling pot and ball milling to obtain micro sheet graphene solution, where the mass ratio of expandable graphite and ion liquid is 1:1-1:5, adding the obtained micro sheet graphene solution into a reactor and sealing, carrying out heat treatment at 240-400 degrees C at pressure of 5-25 MPa for 10-60 minutes, and removing the pressure of the reactor to obtain the graphene.