▎ 摘　　要

NOVELTY - Synthesizing sulfur-doped graphene quantum dots comprises: adding pyrene into fuming nitric acid, stirring by refluxing, then cooling naturally; filtering the resultant reaction material via microporous membrane to remove waste, washing the filtrate using deionized water; adding sodium hydroxide into above material, dispersing ultrasonically, then immediately placing in a high-temperature reactor, reacting using hot water, then cooling naturally; filtering the resultant reaction material via 0.22 mu m microporous membrane to remove solid impurities, dialyzing, evaporating and drying. USE - The method is useful for synthesizing sulfur-doped graphene quantum dots (claimed). ADVANTAGE - The method is simple and economical, and produces sulfur-doped graphene quantum having good luminous performance. DETAILED DESCRIPTION - Synthesizing sulfur-doped graphene quantum dots comprises: (i) adding 1 g pyrene into 80-100 ml fuming nitric acid, stirring by refluxing at 80-100 degrees C for 12 hours, then cooling naturally; (ii) filtering the resultant reaction material via 0.22 mu m microporous membrane to remove waste, washing the filtrate for 3-5 times using deionized water; (iii) adding 0.2-0.6 g sodium hydroxide into above material, dispersing ultrasonically at 300 W for 1 hour, then immediately placing in a high-temperature reactor, reacting at 180-200 degrees C using hot water for 10-12 hours, then cooling naturally; (iv) filtering the resultant reaction material via 0.22 mu m microporous membrane to remove solid impurities, dialyzing via 3500 Da dialysis bag for 48 hours to remove excess reactant ions, evaporating and drying at 70 degrees C to obtain graphene quantum dots; (v) adding 0.1 g resultant graphene quantum dots into 180-220 ml deionized water, degrading ultrasonically at 300 W for 10 minutes, dissolving the graphene quantum dots in deionized water, stirring under magnetic condition, slowly adding 0.25 g sublimed sulfur, stirring for 30 minutes for dispersion of sulfur in graphene quantum dot solution; (vi) transferring the solution into a polytetrafluoroethylene-lined high-temperature reactor, carrying out hydrothermal reaction at 150-200 degrees C for 24 hours, then cooling naturally; and (vii) filtering the resultant reaction material via 0.22 mu m microporous membrane to remove solid impurities, dialyzing via 3500 Da dialysis bag for 48 hours to remove excess reactant ions, evaporating and drying at 70 degrees C to obtain sulfur-doped graphene quantum dots having a particle diameter of 4-6 nm.