▎ 摘　　要

NOVELTY - A single layer graphene is prepared by preparing graphite oxide and expanding it in muffle furnace at 900-1000 degrees C for 15-30 seconds to obtain expanded graphite; adding anhydrous ethanol to disperse the graphite and performing 1 hour ultrasonic treatment; adding hydrazine hydrate (50%), and uniformly stirring; performing hydrothermal reaction at 100 degrees C for 24 hours and filtering, and separating and washing the sample; and drying in vacuum baking oven at 60 degrees C to obtain finished product. USE - Method for preparation of single layer graphene (claimed). ADVANTAGE - The method is capable of providing single layer graphene with high carbon oxygen ratio at high yield, and can be applied in large scale production. DETAILED DESCRIPTION - Preparation of single layer graphene comprises: (A) adding 98% of concentrated sulfuric acid and 98% of concentrated nitric acid into dry reactor, and cooling them to 0 degrees C; adding crystalline flake graphite while stirring, a mass ratio of the concentrated sulfuric acid to the graphite being 7-8:1, and uniformly stirring them; slowly adding potassium permanganate, a mass ratio of potassium permanganate to graphite being 1.5-2:1 and the reaction temperature being controlled at less than or equal to 15 degrees C, and stirring for 10 minutes; putting the reactor into a constant temperature water bath at 35 degrees C and uniformly stirring and reacting for 2 hours; adding deionized water within 30 minutes, a mass ratio of graphite to deionized water being 1:20-30, and the reaction temperature being controlled below 100 degrees C, and adding deionized water to stop the reaction while adding hydrogen peroxide aqueous solution (30%), a mass ratio of the graphite to the hydrogen peroxide aqueous solution being 1:1.5-2; and using 5% of hydrochloric acid and deionized water to wash until no sulfate ion exists, and drying in a baking oven at 60 degrees C for 24 hours to obtain graphite oxide; and (B) taking graphite oxide and expanding it in muffle furnace at 900-1000 degrees C for 15-30 seconds to obtain expanded graphite; adding anhydrous ethanol to disperse the graphite, in which 1 g graphite oxide needs 20 ml of anhydrous ethanol, and performing 1 hour ultrasonic treatment; adding hydrazine hydrate (50%), a mass ratio of the expanded graphite to hydrazine hydrate being 1:8-12, and uniformly stirring; performing hydrothermal reaction at 100 degrees C for 24 hours and filtering, and separating and washing the sample; and drying in vacuum baking oven at 60 degrees C to obtain finished product.