Nitrogen and Sulfur Co-doped Carbon Dots as a Turn-Off Fluorescence Probe for the Detection of Cerium and Iron

Recent advances in II–VI group semiconductor- and carbon-based quantum dots for fluorescence-based sensing of metal ions in water

“…The presence of Hg 2+ ions quenched the fluorescence of the Au NCs through high-affinity metallophilic Hg 2+ –Au + interactions, which switched off the red fluorescence of the Au NCs and provided only blue fluorescence from the unaffected CQDs. Pei et al 92 also demonstrated detection of Ce 4+ and Fe 3+ using S and N co-doped CQDs, where the detection of Ce 4+ was due to the inner filter effect; however, for Fe 3+ , it was observed to be via dynamic quenching.…”