▎ 摘　　要

NOVELTY - Preparing nitrogen-doped graphene quantum dot involves using nitrogen-doped graphene quantum dots by hydrothermal reaction of an aqueous solution containing aminophosphonium under alkaline conditions. USE - Method for preparing nitrogen-doped graphene quantum dots in preparing a kit for detecting iron ions or cytochrome C and for preparing electrochemical light-emitting probe (all claimed). ADVANTAGE - The method enables to prepare nitrogen-doped graphene quantum dots that has electrochemical luminescence properties in sensitive electrochemical sensing system.