Academic Journal of Materials & Chemistry, 2024, 5(3); doi: 10.25236/AJMC.2024.050302.
Lingyu Song1,2, Cheng Pu2, Lingling Ren2, Jingji Zhang1
1College of Materials and Chemistry, China Jiliang University, Hangzhou, Zhejiang, China
2Technology Innovation Center of Graphene Metrology and Standardization for State Market Regulation, National Institute of Metrology (NIM), Beijing, China
Carbon quantum dots (CQDs) demonstrate significant capability for detecting heavy metal ions owing to their affordability, excellent water solubility, and photostability. Additionally, doping of CQDs with nitrogen atoms can introduce excellent electronic, chemical, and optical properties. Therefore, we used CA and EDA as precursors to prepare nitrogen-doped carbon quantum dots (N-CQDs) via a one-step hydrothermal process. They display a maximum emission peak at 443 nm with a quantum yield of fluorescence of 66.7%. The experiment clarified the formation process and described their fluorophore structures. Additionally, the N-CQDs demonstrate outstanding selectivity and sensitivity towards mercury ions (Hg²⁺). Consequently, a fluorescent detection method for Hg²⁺ was developed, which exhibits a broad linear detection range of 0 - 100 μmol·L⁻¹ with a low limit of detection of 4 nM. Furthermore, the fluorescence quenching mechanism was further elucidated, and the potential utilization of this method for detecting Hg²⁺ in tap water samples was also confirmed.
N-CQDs; mercury ions; fluorescent probe
Lingyu Song, Cheng Pu, Lingling Ren, Jingji Zhang. Study on Luminescence Mechanism of Nitrogen-doped Carbon Quantum Dots and Application in Hg2+ Detection. Academic Journal of Materials & Chemistry (2024) Vol. 5, Issue 3: 9-16. https://doi.org/10.25236/AJMC.2024.050302.
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