Green Synthesis of Fluorescent Carbon Quantum Dots for Detection of Hg2+ / 分析化学

Fluorescent carbon quantum dots ( CQDs) were synthesized by one-step hydrothermal treatment of apple juice. Experiments showed that Hg2+could quench the fluorescence of the CQDs with specificity. Based on this phenomenon, a selective and sensitive sensor was constructed for Hg2+ detection. In a NaH2 PO4-Na2HPO4 buffer solution (pH 7. 0), their fluorescence intensity showed good linear relationship with the concentrations of Hg2+ from 5 to 100 nmol/L and 1 to 50 μmol/L, respectively, with the detection limit of 2. 3 nmol/L (S/N=3). Its practical application was further demonstrated by the detection of Hg2+ in real water samples.