▎ 摘　　要

NOVELTY - Preparation of graphene quantum dot involves preparing graphene oxide by Hummers method, dispersing resultant in distilled water, obtaining a graphene oxide aqueous solution, ultrasonically dispersing for 1-3 hours, obtaining a graphene oxide dispersion having concentration of 1-3 mg/L, mixing resultant with hydrogen peroxide and solution (s1) comprising 0.1-10 mmol/L trivalent iron, stirring, adjusting pH of resultant mixture to 3-10, ultrasonically processing resultant mixture under electromagnetic stirring condition, irradiating using mercury lamp at 180-500 nm, and drying at 80 degrees C. USE - Preparation of graphene quantum dot (claimed). ADVANTAGE - The method enables efficient preparation of ultra-small-sized graphene quantum dot having excellent uniformity, with controllable particle size and morphology. DETAILED DESCRIPTION - Preparation of graphene quantum dot involves preparing graphene oxide by Hummers method, dispersing resultant in distilled water, obtaining a graphene oxide aqueous solution, ultrasonically dispersing for 1-3 hours, obtaining a graphene oxide dispersion having concentration of 1-3 mg/L, mixing resultant with hydrogen peroxide and solution (s1) comprising 0.1-10 mmol/L trivalent iron, stirring, adjusting pH of resultant mixture to 3-10, ultrasonically processing resultant mixture under electromagnetic stirring condition, irradiating using mercury lamp at 180-500 nm, and drying at 80 degrees C. The volume ratio of graphene oxide dispersion and trivalent iron solution is 10:1. The volume ratio of hydrogen peroxide and trivalent iron solution is 0.1-4 mol/L.