▎ 摘 要
Nitrogen-doped graphene quantum dots (N-GQDs) were synthesized by direct electrolysis of a carbon cloth electrode coated with nitrogen-doped nanomesh graphene (NG) in high yield (similar to 25%). The N-GQDs emit intense blue fluorescence with a quantum yield (QY) of 10%3%. Meanwhile, the N-GQDs are rich in hydroxyl, carboxyl, basic pyridinic nitrogen, and nitro groups, which are conducive to strengthen the interaction between N-GQDs and Fe3+ for highly sensitive determination of Fe3+ ions. Specifically, the determination for Fe3+ was conducted at different concentrations of N-GQD solution with a wide linear range of 10-1000 mu M (150 mu gmL(-1)) and a low detection limit of 0.19 mu M (10 mu gmL(-1)). Moreover, the fluorescence quenching mechanism illustrated that the functional groups generated by electrochemical oxidation enhanced the interaction of N-GQDs and Fe3+, and the narrow band gap (2.83 eV) of N-GQDs accomplished electron transfer from N-GQDs to Fe3+ easily.