▎ 摘　　要

NOVELTY - Potassium permanganate is dissolved in distilled water, potato starch is added, stirred, subjected to hydrothermal treatment, filtered, washed with anhydrous ethanol and distilled water, and dried, to obtain sheet-shaped hexagonal manganese dioxide. The obtained product is added to graphite oxide dispersion, mixed, subjected to hydrothermal treatment, cooled, filtered, washed with anhydrous ethanol and distilled water, and dried, to obtain sheet-shaped hexagonal manganese dioxide/graphene/porous carbon composite material. USE - Preparation of sheet-shaped hexagonal manganese dioxide/graphene/porous carbon composite material used as supercapacitor electrode material (claimed). ADVANTAGE - The method enables environmentally-friendly, simple, stable, easy and economical preparation of lightweight, renewable, reliable and high-quality sheet-shaped hexagonal manganese dioxide/graphene/porous carbon composite material having excellent synergistic effect. The supercapacitor using the sheet-shaped hexagonal manganese dioxide/graphene/porous carbon composite material has excellent electrochemical capacitance, rate characteristics and cycle characteristics. DETAILED DESCRIPTION - Graphite oxide is dispersed in distilled water, to obtain graphite oxide dispersion with concentration of 1-1.5 mg/mL. Potassium permanganate is dissolved in distilled water, potassium permanganate aqueous solution with concentration of 0.05-0.1 g/L is obtained, potato starch is added, stirred, pH of obtained mixed solution is adjusted to 9-10, subjected to hydrothermal treatment at 160-180 degrees C for 12-24 hours, cooled to room temperature, filtered, washed with anhydrous ethanol and distilled water until neutral, and dried, to obtain sheet-shaped hexagonal manganese dioxide. The obtained product is added to graphite oxide dispersion, mixed, subjected to hydrothermal treatment at 160-180 degrees C for 12-24 hours, cooled to room temperature, filtered, washed with anhydrous ethanol and distilled water until neutral, and dried, to obtain sheet-shaped hexagonal manganese dioxide/graphene/porous carbon composite material. An INDEPENDENT CLAIM is included for use of sheet-shaped hexagonal manganese dioxide/graphene/porous carbon composite material as supercapacitor electrode material.