In this paper, a novel synthesis of 1 nm sized metal-free carbon quantum dots (CQDs) and their electrochemical application vis-à-vis mercury (Hg) sensing have been demonstrated. The characterization of synthesized CQDs was done by FT-IR, HR-TEM, XRD and UV–Vis analysis. Furthermore, the CQD-modified electrode shows an excellent sensing ability toward deleterious Hg ion even when 600-fold of excess of interfering ions such as Cu2+, Pb2+, Cd2+, Na+, K+, Mg2+, Ba2+, Bi2+, Fe2+, Zn2+ and Hg2+ are present. A wide linearity range (0.5–300 nM) and the lowest limit of detection (2.5 nM) are exhibited by the proposed sensor with potential scanning from − 0.7 to + 0.7 V vs Ag/AgCl at a scan rate of 20 mV. In addition, the CQD-modified electrode displays an outstanding recovery results toward Hg in various real water samples. This study promotes new possibilities of designing various electrochemical sensors based on CQD nanocomposite. Fast detection of mercury ion by electrochemical method. One-pot synthesis of CQDs from activated carbon obtained from coconut shell. Both selective and sensitive nature of CQD-modified electrode. Anti-interference ability, stability, and reproducibility of the CQD-modified electrode are highly good. Fast detection of mercury ion by electrochemical method. One-pot synthesis of CQDs from activated carbon obtained from coconut shell. Both selective and sensitive nature of CQD-modified electrode. Anti-interference ability, stability, and reproducibility of the CQD-modified electrode are highly good.

中文翻译：

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利用碳量子点改性玻碳电极对有毒汞离子进行高选择性和灵敏检测

在本文中，已经证明了 1 nm 大小的无金属碳量子点 (CQD) 的新合成及其电化学应用相对于汞 (Hg) 传感。通过 FT-IR、HR-TEM、XRD 和 UV-Vis 分析对合成的 CQD 进行表征。此外，即使当干扰离子如 Cu2+、Pb2+、Cd2+、Na+、K+、Mg2+、Ba2+、Bi2+、Fe2+、Zn2+ 和 Hg2+ 过量 600 倍时，CQD 修饰的电极仍显示出对有害 Hg 离子的出色传感能力。展示。所提出的传感器具有较宽的线性范围 (0.5–300 nM) 和最低检测限 (2.5 nM)，其电位扫描范围为 - 0.7 至 + 0.7 V vs Ag/AgCl，扫描速率为 20 mV。此外，CQD 修饰的电极在各种实际水样中对 Hg 显示出出色的回收率。这项研究促进了设计基于 CQD 纳米复合材料的各种电化学传感器的新可能性。电化学法快速检测汞离子。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。电化学法快速检测汞离子。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。电化学法快速检测汞离子。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。电化学法快速检测汞离子。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。从椰子壳中获得的活性炭一锅法合成 CQD。CQD 修饰电极的选择性和敏感性。CQD修饰电极的抗干扰能力、稳定性和重现性非常好。