▎ 摘　　要

NOVELTY - Preparation of graphene quantum dot comprises adding graphene oxide in 50 ml of 1 mg/ml potassium permanganate (KMnO4), ultrasonically processing for 4 hours, centrifuging at 3000 revolutions/minute (rpm) for 30 minutes, taking the supernatant, continuously centrifuging at 10000 rpm and obtaining the product. USE - Preparation of graphene quantum dot (claimed). ADVANTAGE - The method has high reproducibility, low energy consumption, short preparation time and high yield and is easy control, simple and environment friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for graphene quantum dot.