▎ 摘　　要

NOVELTY - Preparing coal-based graphene quantum dots, comprises crushing natural coal into powder, sieving through 200 mesh sieve, dispersing sieved material uniformly in N,N-dimethyl formamide and placing in ultrasonic cell crusher, carrying out ultrasonic crushing in ultrasonic cell crusher at an actual output power of 195-600 W for 2-6 hours at room temperature under normal pressure, then filtering through 0.22 mu m polytetrafluoroethylene filter film to obtain yellow clear solution, and removing N,N-dimethyl formamide by dialysis to obtain final product. USE - The method is useful for preparing coal-based graphene quantum dots (claimed). ADVANTAGE - The method: has simple operation, low cost; avoids chemical oxidation and reduces fluorescence intensity of Coal - based graphene quantum dots.