▎ 摘　　要

NOVELTY - Preparation of graphene/metal oxide three-dimensional composite material involves taking natural graphite and potassium permanganate, adding 98% sulfuric acid, stirring in ice bath for 1-2 hours, heating to 35 degrees C, adding deionized water, heating at 90-95 degrees C for 30-35 minutes, naturally cooling to room temperature, adding 35% hydrogen peroxide, stirring at room temperature at speed of 100-300 rpm, centrifugally separating at speed of 3000-3500 rpm, taking upper layer clear liquid, centrifugally separating, taking upper layer clear liquid, centrifugally separating and drying. USE - Method for preparing graphene/metal oxide three-dimensional composite material (claimed). ADVANTAGE - The composite material has electric current density of 100 mA/g, reversible capacity of 800-1300 Ah/g and holding capacity of 70-98%. DETAILED DESCRIPTION - Preparation of graphene/metal oxide three-dimensional composite material comprises: (A) taking natural graphite and potassium permanganate, adding 98% sulfuric acid, stirring in ice bath for 1-2 hours at speed of 300-400 revolutions/minute (rpm), heating to 35 degrees C, adding deionized water, heating at 90-95 degrees C for 30-35 minutes, naturally cooling to room temperature, adding 35% hydrogen peroxide, stirring at room temperature at speed of 100-300 rpm, centrifugally separating at speed of 3000-3500 rpm, taking upper layer clear liquid, centrifugally separating at speed of 8000-8500 revolutions/minute and drying at 60-80 degrees C for 1-3 hours to obtain graphene oxide; (B) taking nickel mesh, adding 1 mol/L hydrochloric acid solution, soaking for 10-20 minutes, taking out, washing with deionized water and anhydrous alcohol for 1-3 times, drying and mixing with aniline and N-methylpyrrolidone; (C) dissolving graphene oxide in water to concentration of 1%, dissolving polystyrene microsphere in water to concentration of 3%, mixing, stirring and reacting for 8-15 minutes at speed of 100-500 rpm, adding metal chloride, stirring and reacting for 8-15 minutes at speed of 100-500 rpm, ultrasonically treating at 200-500 W for 30 minutes, stirring and reacting for 8-15 minutes at speed of 100-500 rpm to obtain mixed solution; and (D) adding nickel mesh to mixed solution, soaking for 1-3 minutes, taking out, freeze-drying at - 65 to - 75 degrees C for 30-40 minutes, putting in tubular furnace, heating at 190-220 degrees C for 60-70 minutes, heating at 600-650 degrees C for 120-150 minutes, cooling to 190-220 degrees C and naturally cooling to room temperature.