Preparation of Nitrogen-doped Fluorescent Carbon Dots and the Detection Performance for MnO4-
Nitrogen-doped fluorescent carbon dots(N-CDs)were prepared by one-step hydrothermal method using ascorbic acid and ethylenediamine.N-CDs were characterized by transmission electron microscope(TEM),ul-traviolent-visible spectroscopy(UV-vis),Fourier transform infrared(FTIR)and fluorescence spectrum.In ad-dition,the response mechanism of N-CDs to MnO4-was investigated.The results showed that the average particle size of N-CDs was 6.41 nm,the dispersion was good with no obvious agglomeration,and the fluo-rescence quantum yield was about 15%.Experiments indicated that N-CDs had the high selectivity and sen-sitivity to MnO4-,and the fluorescence quenching degree had a good linear relationship with the molar con-centration(0~60 μmol/L)of MnO4-.The detection limit of N-CDs to MnO4-was 0.055 µmol/L,and the fluorescence quenching mechanism of MnO4-on N-CDs was dynamic quenching.N-CDs can be used as fluo-rescence sensor to provide a sensitive method for the detection of MnO4-in water.