▎ 摘　　要

NOVELTY - A graphene-ionic liquid composite material preparing method involves adding potassium permanganate and graphite to concentrated sulfuric acid and stirring the mixture. Deionized water is added to the mixture under ice bath condition, followed by adding hydrogen peroxide solution to the mixture, filtering the mixture, washing obtained solid with hydrochloric acid, filtering graphite oxide, and adding the graphite oxide to ionic liquid. The obtained mixture is centrifuged. USE - Method for preparing graphene-ionic liquid composite material that is utilized in preparing supercapacitor (claimed). ADVANTAGE - The method enables preparing graphene-ionic liquid composite material in short reaction time, with uniform graphite component and uniformly dispersed ionic liquid, preventing re-agglomeration of graphene, and maintaining relatively high energy of graphene-ionic liquid composite material than capacity. DETAILED DESCRIPTION - A graphene-ionic liquid composite material preparing method involves adding potassium permanganate and graphite to concentrated sulfuric acid at 0 degrees C, stirring the mixture at 10 degrees C for 2 hours, and stirring the mixture at low room temperature for 24 hours. Deionized water is added to the mixture under ice bath condition, followed by adding hydrogen peroxide solution to the mixture after 15 minutes, filtering the mixture, washing obtained solid with hydrochloric acid, filtering graphite oxide, and adding the graphite oxide to ionic liquid at 150-300 degrees C for 30-300 minutes under microwave conditions. The obtained mixture is centrifuged for 30 minutes to separate unreacted liquid to obtain graphene-ionic liquid composite material. The mass volume ratio of the graphite oxide and ion liquid is 1 g:10-100 ml. An INDEPENDENT CLAIM is included for a method for preparing supercapacitor, which involves placing the obtained graphene-ionic liquid composite material in a mold, applying constant pressure to graphene-ionic liquid composite material, cooling the graphene-ionic liquid composite material to room temperature, and opening the mold to obtain electrode plate. Diaphragm is immersed in the ionic liquid. The electrode plates are assembled in order to obtain a laminated electric core, followed by covering with a shell to obtain the super capacitor.