▎ 摘　　要

NOVELTY - Composite comprises reduced graphene oxide sheet including cobalt oxide nanoparticles; and manganese dioxide nanowire formed on the surface of the reduced oxidized graphene sheet and inserted between the cobalt oxide nanoparticles. USE - The composite is useful in electrode for supercapacitor (claimed). ADVANTAGE - The method is simple. The composite has excellent cyclic stability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for producing composite, comprising (a) preparing reduced oxidized graphene sheet including cobalt oxide nanoparticles, (b) dispersing the reduced oxidized graphene sheet in water, and ultrasonifying to prepare suspension, (c) adding potassium permanganate into the prepared suspension, and stirring, (d) adding the stirred reaction mixture into an autoclave, heating, and cooling to room temperature, and (e) washing the cooled reaction mixture, and drying.