▎ 摘　　要

NOVELTY - Preparing nitrogen-doped graphene/activated carbon composite material involves adding concentrated acid and graphite powder and mixing, adding potassium permagnate and mixing and reacting, adding powder pitch coke and continuing the mixing reaction. The pure water is added to continue the mixing reaction. The hydrogen peroxide is added to terminate the reaction, and the mixture is obtained after the reaction is completed. The above mixture is filtered and washed, added a small molecular nitrogen source, and dispersed uniformly in water ultrasonically to obtain a suspension, spray-dried the suspension to obtain a nitrogen-doped graphene oxide/pitch coke composite powder. The nitrogen-doped graphene oxide/pitch coke composite powder is taken and mixed with alkali. USE - Method for preparing nitrogen-doped graphene/activated carbon composite material used in the preparation of supercapacitor electrode materials (claimed). ADVANTAGE - The method enables to prepare nitrogen-doped graphene/activated carbon composite material that has simple operation. DETAILED DESCRIPTION - Preparing nitrogen-doped graphene/activated carbon composite material involves adding concentrated acid and graphite powder and mixing, adding potassium permagnate and mixing and reacting, adding powder pitch coke and continuing the mixing reaction. The pure water is added to continue the mixing reaction. The hydrogen peroxide is added to terminate the reaction, and the mixture is obtained after the reaction is completed. The above mixture is filtered and washed, added a small molecular nitrogen source, and dispersed uniformly in water ultrasonically to obtain a suspension, spray-dried the suspension to obtain a nitrogen-doped graphene oxide/pitch coke composite powder. The nitrogen-doped graphene oxide/pitch coke composite powder is taken and mixed with alkali. The activated material is activated at high temperature under the protection of an inert atmosphere, and the activated material is washed, filtered, dried and pulverized to obtain a nitrogen-doped graphene/activated carbon composite material. An INDEPENDENT CLAIM is included for a method for preparing supercapacitor electrode materials, which involves mixing nitrogen-doped graphene/activated carbon composite material, conductive agent and binder in ratio (90-94): (1-4): (4-6), where the binder is polytetrafluoroethylene or a mixture of hydroxymethyl cellulose and styrene-butadiene rubber, and the conductive agent is conductive carbon black.