▎ 摘　　要

NOVELTY - Method for preparing nitrogen atom-doped graphene quantum dot, involves (a) preparing nitrogen-doped carbon nanotube/nitrogen-doped graphene three-dimensional hybrid material with nickel foam as substrate as precursor, (b) placing obtained precursor prepared in two-electrode system with 0.1-0.3 mol/l ammonia solution as electrolyte at a current of 0.01 (A), reacting for 4-8 hours, using precursor as working electrode, and using platinum sheet as counter electrode, and (c) after completing the reaction, filtering reaction solution, and performing rotary evaporation to obtain nitrogen atom-doped graphene quantum dots. USE - Method for preparing nitrogen atom-doped graphene quantum dot (claimed) used in biosensors, photocatalysis and supercapacitors. ADVANTAGE - The method ensures nitrogen doping content of the graphene quantum dots as high as 18% and fluorescence quantum yield of graphene quantum dots as high as 19.3%, improves the chemical properties and electron transport of quantum dots, and is simple and environmentally-friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a graphene quantum dot doped with nitrogen atoms prepared using above-mentioned method, which comprising nitrogen doping amount of obtained graphene quantum dots of 18%, and fluorescence quantum yield of 19.3%.