▎ 摘　　要

NOVELTY - Preparation of graphene quantum dot, involves adding phloroglucinol solution to a hydrothermal reactor, placing in a blast dryer, reacting at 160-220 degrees C for 2-15 hours, preferably at 180 degrees C for 8 hours, cooling naturally to obtain a brownish yellow solution, adding the solution to a centrifugal tube, and centrifuging at 3000-15000 rpm to obtain a brownish yellow clear and transparent supernatant as aqueous solution of graphene quantum dots. USE - Preparation of graphene quantum dots for use in optoelectronic device and biomedicine. ADVANTAGE - The method does not use a strong acid or strong alkali oxidant or any other chemical reagents, is simple, efficient, safe and environmentally-friendly, and can be carried out industrially on a large scale. The obtained graphene quantum dots have stable fluorescence, and excellent water solubility and biocompatibility.