▎ 摘　　要

NOVELTY - Graphene oxide/manganese dioxide precursor is ultrasonically dispersed in distilled water, aqueous solution of reducing agent is added, maintained for 8-24 hours and reacted at 60-90 degrees C for 2 hours. The resultant reaction solution is subjected to suction filtration, repeatedly washed with distilled water, temperature is controlled to 50-65 degrees C and dried, to obtain graphene/manganese tetroxide composite electrode material. The reducing agent is hydrazine hydrate or sodium borohydride. The mass ratio of reducing agent and graphene oxide/manganese dioxide precursor is 10:1. USE - Preparation of graphene/manganese tetroxide composite electrode material used for supercapacitor. ADVANTAGE - The method provides graphene/manganese tetroxide composite electrode material by a simple process without requiring the expensive equipment. DETAILED DESCRIPTION - Graphene oxide and manganese chloride tetrahydrate in mass ratio of 1:20, are added into isopropanol, mixed uniformly and ultrasonically dispersed, to obtain mixed solution of graphene oxide and manganese chloride. The obtained mixed solution is placed in 80 degrees C water bath, 75.5 g/L aqueous solution of potassium permanganate is added, reacted at 83 degrees C for 30 minutes, the resultant reaction solution is subjected to suction filtration, the filter cake is washed with distilled water and temperature is controlled to 50-65 degrees C and dried, to obtain graphene oxide/manganese dioxide precursor. The mass ratio of manganese chloride tetrahydrate and potassium permanganate is 1.854:1. The obtained precursor is ultrasonically dispersed in distilled water, aqueous solution of reducing agent is added, maintained for 8-24 hours and reacted at 60-90 degrees C for 2 hours. The resultant reaction solution is subjected to suction filtration, repeatedly washed with distilled water, temperature is controlled to 50-65 degrees C and dried, to obtain graphene/manganese tetroxide composite electrode material. The reducing agent is hydrazine hydrate or sodium borohydride. The mass ratio of reducing agent and graphene oxide/manganese dioxide precursor is 10:1.