Nitrogen and Sulfur Codoped Carbon Dots Graphitic Carbon Nitride Composites for Fluorescence Sensing of Mercury Ions

Authors:
Publisher website
Google Scholar
Abstract
A facile “turn‐off” fluorescence sensing approach based on nitrogen and sulfur codoped carbon dots intercalated into graphitic carbon nitride (N, S‐CDs@gC 3 N 4 ) has been developed for the selective and sensitive detection of mercury ions (Hg 2+ ). The sensor offers the synergistic interaction between N, S‐CDs and gC 3 N 4 , where nitrogen and sulfur doping not only enhances fluorescence properties but also promotes strong Hg‐S and Hg‐N binding affinity. Upon interaction with Hg 2+ the fluorescence of the N, S‐CDs@gC 3 N 4 composite is significantly quenched via static quenching mechanism (excitation/emission at 370/425 nm). The sensor shows a linear response to Hg 2+ in the range of 1.0–7.2 μM ( R 2 = 0.99) with a limit of detection of 0.421 μM. The method was successfully applied to detect Hg 2+ in spiked tap and canal water samples at concentrations of 1.01, 2.84, and 4.47 µM, yielding recoveries of 98.89%–99.21% (RSD: 0.74%–2.26%) for tap water and 96.76%–98.03% (RSD: 0.61%–1.59%) for canal water. These results demonstrate the potential of N, S‐CDs@gC 3 N 4 for real‐time application of Hg 2+ .

This publication has 27 references indexed in Scilit: