▎ 摘　　要

NOVELTY - Preparing graphene comprises (i) adding graphite oxide into water and ultrasonic dispersing to obtain graphene oxide suspension with concentration of 1-20 mg/ml; (ii) adding 1-500 g/l potassium hydroxide solution into graphene oxide suspension, and stirring to obtain condensed type solution; (iii) adding 1-500 g/l sodium hydroxide solution and stirring for 1-5 hours to obtain mixed solution; and (iv) filtering, drying, placing dried filtrate in a muffle furnace, high-temperature calcining under inert atmosphere, cooling, acid washing, water washing, filtering and drying to obtain graphene. USE - The graphene is useful in super capacitor (claimed). ADVANTAGE - The method is simple, reduces production cost and produces multi-property graphene material in single step. The graphene has high specific surface area, high electrical conductivity, and increases energy density and power density of the super capacitor. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) graphene prepared by the above method; (2) electrode sheet, comprising a current collector and an activated material coated on the surface of the current collector, where the activated material comprises graphene, polyvinylidene fluoride as adhesive and acetylene black as conductive agent according to mass ratio of 88:10:2; and (3) super capacitor, comprising the electrode sheet.