▎ 摘　　要

NOVELTY - The preparation of graphene involves adding concentrated sulfuric acid to graphite and potassium permanganate, heating, adding water, heating, adding hydrogen peroxide, diluting with water to obtain oxidized graphite diluent, ultrasonically treating to obtain suspension, allowing suspension to settle, removing supernatant, washing suspension with hydrochloric acid and ethanol, removing supernatant, lyophilizing suspension, obtaining brown graphene oxide powder, treating using microwave, expanding oxidized graphene powder, annealing, filling ammonia and cooling. USE - Preparation of large specific surface area nitrogen-doped graphene (claimed) used for electrochemical catalysis and super capacitor. ADVANTAGE - The method improves the synthesis efficiency of nitrogen-doped graphene with less energy consumption. DETAILED DESCRIPTION - The preparation method of nitrogen-doped graphene involves weighing graphite raw materials and potassium permanganate, adding concentrated sulfuric acid to the mixture of graphite and potassium permanganate, evenly mixing, stirring at 0-2 degrees C for 60-120 minutes, adjusting the temperature to 30-40 degrees C, heating, stirring for 60-120 minutes, adding deionized water, stirring, increasing the temperature to 90-95 degrees C, heating for 5-15 minutes, adding hydrogen peroxide, diluting again with deionized water to obtain oxidized graphite diluent, ultrasonically treating the resulting oxidized graphite diluent to obtain suspension, allowing the suspension to settle, removing the supernatant, washing the suspension with hydrochloric acid and ethanol, removing supernatant fluid, repeatedly using deionized water on the suspension for washing sedimentation, removing the supernatant, lyophilizing the suspension, until the suspension is neutral, obtaining brown graphene oxide powder, carrying out microwave treatment of graphene oxide powder under vacuum, expanding 40-60 wt.% oxidized graphene powder 2-3 times after microwave treatment, annealing the oxidized graphene powder after microwave treatment is carried out at the heating rate of 4-8 degrees C/minutes, increasing the temperature rose to 800 degrees C for 20-60 minutes, heat preserving at 800 degrees C for 20-60 minutes, filling ammonia, maintaining the flow rate to 1-30 torr for 30-180 minutes and spontaneously cooling to room temperature under vacuum. An INDEPENDENT CLAIM is included for the graphene.