▎ 摘　　要

NOVELTY - Sulfonated graphene is prepared by mixing ammonium sulfate and graphene oxide at mass ratio of 1:1-20, dissolving mixture in deionized water and ultrasonically dispersing for 10-60 minutes; performing rotary evaporation to the solution to remove water; and freeze-drying the obtained precipitate, and then heating to 100-300 degrees C under protection of argon gas or nitrogen atmosphere for 30-60 minutes to obtain black fluffy sulfonated graphene powder. USE - Method of preparing sulfonated graphene (claimed). ADVANTAGE - The method has simple operation process and good graphene oxide dispersion in the drying step, and can reduce the graphene oxide by sulfonation to improve conductivity of sulfonated graphene.