▎ 摘　　要

NOVELTY - A single-layered graphene is prepared by preparing single-layered oxidized graphite slice solution and oxidized graphene solid, and preparing single-layered graphene. The preparation of single-layered oxidized graphite slice solution and oxidized graphene solid by centrifuging single-layered oxidized graphite slice solution, drying solid in vacuum to obtain graphene solid. The preparation of single-layered graphene by dispersing graphene solid into dimethyl sulfoxide solution, mixing and transferring into reaction kettle; and keeping reaction, filtering to obtain single-layered graphene. USE - Method for preparation of single-layered graphene (claimed). ADVANTAGE - The method is simple and non-toxic, and is environment-friendly and convenient to operate with low production cost. DETAILED DESCRIPTION - The single-layered graphene is prepared by preparing single-layered oxidized graphite slice solution and oxidized graphene solid, and preparing single-layered graphene. The preparation of single-layered oxidized graphite slice solution and oxidized graphene solid involves: (A) taking natural graphite powder as material, adding concentrated sulfuric acid, potassium persulfate and phosphorus pentoxide, uniformly mixing at 80 degrees C, and reacting for 4.5 hours; (B) cooling mixture to room temperature, diluting with deionized water, and standing overnight; (C) filtering, separating with acetic acid cellulose film of 0.2 mu m, washing with deionized water, and standing at room temperature overnight; (D) mixing pre-oxidized graphite while adding into mixed solution of cold concentrated sulfuric acid and potassium hypermanganate; (E) mixing at 35 degrees C and diluting with deionized water, and keeping mixing and adding hydrogen peroxide solution; (F) filtering solution and washing metal ion with diluted hydrochloric acid, washing excess acid with deionized water and washing with water until becomes neutral; (G) dialyzing product for one week to remove residual metal ion; (H) obtaining oxidized graphite, preparing into 0.5 mg/ml of aqueous solution, and ultrasonic treating in ultrasonic machine to obtain brown uniformly distributed single-layered oxidized graphite slice solution; and (I) centrifuging and separating single-layered oxidized graphite slice solution in high-speed centrifuge, drying obtained solid in vacuum to obtain oxidized graphene solid. The preparation of single-layered graphene involves dispersing oxidized graphene solid into dimethyl sulfoxide solution at mass ratio of 1:1, uniformly mixing and transferring mixture into reaction kettle; and keeping reaction at 150-200 degrees C for 10-16 hours, filtering to obtain black product as single-layered graphene, and storing product in a vacuum and dry place.