▎ 摘　　要

NOVELTY - Detection of trivalent iron ions involves placing nitrilotriacetic acid powder in a reaction container with a polytetrafluoroethylene substrate under a nitrogen atmosphere, heating to 200-260 degrees C for solid-phase decomposition, ultrasonically dissolving the product in absolute ethanol, separating unreacted nitrilotriacetic acid and nitrogen-doped graphene quantum dots by centrifugation, removing ethanol by evaporation, dissolving nitrogen-doped graphene quantum dots in water to obtain an aqueous solution of nitrogen-doped graphene quantum dots, adding a to-be-measured iron ion solution to the aqueous solution, detecting the fluorescence intensity, and calculating the iron ion in the iron ion solution according to the linear relation between the fluorescence intensity and the iron ion concentration. USE - Detection of trivalent iron ions. ADVANTAGE - The trivalent iron ions can be detected quickly with high sensitivity and selectivity with low detection limit.