▎ 摘　　要

NOVELTY - Preparation of graphene powder, involves (i) adding graphite and potassium nitrate to sulfuric acid and stirring, (ii) adding potassium permanganate, and stirring, performing oxidation, then adding deionized water, heating, and continually stirring, (iii) adding deionized water, adding hydrogen peroxide, treating until the suspension becomes bright yellow, and obtaining graphite oxide, (iv) washing the graphite oxide several times, and obtaining uniformly dispersed oxidized graphene hydro-sol, (v) heating the oxidized graphene hydro-sol at an inlet temperature and spray drying. USE - Preparation of graphene powder (claimed). ADVANTAGE - The prepared graphene powder has excellent dispersibility and controllable size. DETAILED DESCRIPTION - Preparation of graphene powder, involves (i) adding 1.0 g graphite and 1.0 g potassium nitrate to 46 ml sulfuric acid and stirring for 10 minutes, (ii) adding 6 g potassium permanganate under the stirring condition, and stirring for 6 hours, performing oxidation, then adding 80 ml deionized water, heating at 90 degrees C, and continually stirring for 30 minutes, (iii) adding 200 ml deionized water after completion of the reaction, adding 6 ml hydrogen peroxide with concentration of 30%, treating until the suspension becomes bright yellow, and obtaining graphite oxide, (iv) washing the graphite oxide several times by centrifuges until neutral to remove impurity ions where in the repeated washing process, the water molecules gradually insert into the oxide layer of graphite, and obtaining uniformly dispersed oxidized graphene hydro-sol, (v) heating the oxidized graphene hydro-sol at an inlet temperature of 200 degrees C, spray drying at 100 degrees C outlet temperature to obtain dried graphene powder, and (vi) placing the oxidized graphene powder into a closed quartz tube at one end, filling the quartz tube with argon and quickly placing in a tube furnace at a temperature of 1050 degrees C, annealing for 30 seconds while rapidly expanding the volume of the graphene powder and obtaining graphene powder.