▎ 摘　　要

NOVELTY - Preparing graphene oxide involves mixing concentrated sulfuric acid and concentrated phosphoric acid in volume ratio of 5:1-10:1 to obtain mixed acid solution, adding into reaction container and adding natural crystalline flake graphite where the ratio of natural crystalline flake graphite and mixed acid is 0.25-2 gram:40 milliliter. The solution is placed in ultrasonic cleaner at 0-20 degrees C, 100-200 Watt for 0.5-1 hours, stirred and the first batch of potassium permanganate is added. USE - Method for preparing graphene oxide used for preparing energy storage material, sensor, super-capacitor, graphene composite material, high strength lightweight composites, catalyst carriers and adsorbent carriers (claimed). ADVANTAGE - The method enables to prepare graphene oxide which is easy to process in quick manner, and saves energy and effectively improves interlayer spacing of graphite oxide. DETAILED DESCRIPTION - Preparing graphene oxide involves mixing concentrated sulfuric acid and concentrated phosphoric acid in volume ratio of 5:1-10:1 to obtain mixed acid solution, adding into reaction container and adding natural crystalline flake graphite where the ratio of natural crystalline flake graphite and mixed acid is 0.25-2 gram:40 milliliter. The solution is placed in ultrasonic cleaner at 0-20 degrees C, 100-200 Watt for 0.5-1 hours, stirred and the first batch of potassium permanganate is added, where the mass ratio of first batch of potassium permanganate and natural crystalline flake graphite is 0.5-2 gram:0.25-2 gram. The mixture is continuously stirred for 5-10 minutes, the reaction container is put into ultrasonic cleaner at 0-20 degrees C, 100-200 Watt for 1-4 hours, stirred and the second batch of potassium permanganate is added, where the ratio of second batch of potassium permanganate and natural flake graphite is 2-6 gram:0.25-2 gram. The mixture is stirred for 5-10 minutes, heated on water bath at 50-80 degrees C and stirred for 2-5 hours. The obtained solution is poured on ice and hydrogen peroxide solution is added, where the mass volume ratio of hydrogen peroxide, ice and natural crystalline flake graphite is 5-10 milliliter: 100-500 milliliter: 0.25-2 gram. The obtained product is centrifugally washing until it is neutral and ultrasonically treated at 100-200 Watt for 2-3 hours to obtain graphene oxide.