▎ 摘　　要

NOVELTY - Graphene paper is prepared by adding graphite to concentrated sulfuric acid, then adding sodium nitrate and potassium permanganate, heating in water bath, quenching to obtain brown graphite suspension, and adding hydrogen peroxide to obtain bright yellow graphene oxide suspension; filtering suspension and drying filter cake to obtain graphene oxide solid; dispersing solid in solvent; casting dispersion on a substrate and drying to obtain graphene oxide film; and leaching the film using ascorbic acid solution for reduction of film and drying reduced film to obtain graphene paper. USE - Method of preparing graphene paper (claimed) used in nanofilter membrane, supercapacitor, or lithium battery. ADVANTAGE - The method is simple and suitable for large scale preparation. The obtained graphene paper has enhanced electrical property, uniform height, shape, size and thickness, and high purity. DETAILED DESCRIPTION - Preparation of graphene paper comprises: (A) adding graphite to concentrated sulfuric acid and uniformly stirring at room temperature, then adding sodium nitrate, cooling, adding potassium permanganate in batches, heating in water bath at 35 plus minus 3 degrees C degrees C, adding ice water and quenching to obtain brown graphite suspension; (B) stirring brown graphite suspension and adding hydrogen peroxide to obtain bright yellow graphene oxide suspension; (C) filtering bright yellow graphene oxide suspension, acid washing the filter cake, then washing with deionized water until no chloride ion in the washing liquid, and drying to obtain graphene oxide solid; (D) dispersing graphene oxide solid in solvent under ultrasonic condition to obtain uniform dispersion of graphene oxide suspension; (E) casting the dispersion of graphene oxide suspension on a substrate and drying to obtain graphene oxide film; and (F) leaching the graphene oxide film using ascorbic acid solution for reduction of film and drying reduced film to obtain graphene paper.