▎ 摘　　要

NOVELTY - Graphene is claimed. USE - Used as a graphene. ADVANTAGE - The graphene is provided with 2-8 layers, specific surface area of 450-800 m2/g, electric conductivity of 20-60 S.m-1, and at 900 degrees C, weight loss of 1-2 wt.% (claimed). The method has simple preparation process, produces high yield product, reduces the production cost, requires less device, and is environmentally friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing graphene, comprising (i) preparing mixed solvent by: adding deionized water and embedding agent in the reaction kettle, stirring at 30-100 revolutions/minute for 0.5-2 hours at 25-35 degrees C, uniformly mixing the solvent, then adding sodium hydroxide or potassium hydroxide, continuing to stir for 0.5-2 hours at 30-100 revolutions/minute at 25-35 degrees C to obtain the mixed solvent, (ii) preparing the crude product by: adding the graphite powder into the mixed solvent, carrying out ultrasonic dispersion treatment at 400-500 W under the frequency of 50 Hz, dispersing for 0.5-1 hour to obtain suspension of graphite powder, separating, washing using water to obtain crude product, (iii) pre-processing the product by: placing the crude product at -60 degrees C to -10 degrees C low temperature for 5-10 hours, transferring to the high temperature reactor and puffing, where the temperature is 150-300 degrees C, collecting the puffing powder, using a high-speed airflow crushing device and processing for 1 hour, (iv) product fine processing by: adding the step (iii) obtained product in aqueous ethanol solution, at 500 W, ultrasonically dispersing under the frequency of 50 Hz for 0.5-1 hour, washing using water, spraying and drying to obtain the product, and (v) repeating the step (iii) and (iv) for many times, and then heating at 350-550 degrees C in a microwave oven for 0.5-1 hour, and taking out layer to obtain the graphene product.