▎ 摘　　要

NOVELTY - A composite material having high density comprises 5-20% reduced graphene oxide having lamellar structure, and 95-80% copper sulfide in form of particles uniformly distributed on surface of graphene sheets. USE - Composite material. ADVANTAGE - The composite material prepared has fine granular shape. The electrochemical reaction can be maximized during the charging and discharging process, so that the specific capacitance of the material is increased. The material reduces the large specific surface area of the graphene oxide, and effectively improves the specific capacity and cycle life of the supercapacitor. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of composite material, which involves using 1 g graphite powder, 50 mL concentrated sulfuric acid, 1g sodium nitrate, potassium permanganate, 30 %mass hydrogen peroxide, and 171 mg copper chloride.