▎ 摘　　要

NOVELTY - Preparing nano graphene involves taking natural crystalline flake graphite as raw material, adding the bonding agent into the crystalline flake graphite, fully mixing and stirring, adding into a mold, heating, applying pressure, keeping for certain time and cooling, where the heating temperature is 100-220 degrees C, applying pressure is 80-100 magaPascal and heat preservation time is 1-3 hours. The obtained graphite block is put into a vacuum induction furnace for high temperature heat treatment at 2500-2800 degrees C with heating rate of 30-50 degrees C/minute for 3-5 hours and slowly cooled to room temperature. USE - Method for preparing nano graphene (claimed). ADVANTAGE - The method enables to prepare nano graphene which is easy to process, eco-friendly and convenient for mass production, and has stable quality. DETAILED DESCRIPTION - Preparing nano graphene involves taking natural crystalline flake graphite as raw material, adding the bonding agent into the crystalline flake graphite, fully mixing and stirring, adding into a mold, heating, applying pressure, keeping for certain time and cooling, where the heating temperature is 100-220 degrees C, applying pressure is 80-100 magaPascal and heat preservation time is 1-3 hours. The obtained graphite block is put into a vacuum induction furnace for high temperature heat treatment at 2500-2800 degrees C with heating rate of 30-50 degrees C/minute for 3-5 hours and slowly cooled to room temperature. The obtained graphite block is subjected to microarc oxidation treatment via high temperature treatment of graphite block and ultrasonically treated to obtain nano graphene sheets, where the oxidation voltage is 250-400 Volts, frequency is 500-1000 Hertz. The electrolyte is mixed solution of sulfuric acid and potassium hydroxide, where the ultrasonic vibration frequency is 20-25 kiloHertz and power is 2-3 kiloWatt.