A specific electrochemiluminescence sensor for selective and ultra-sensitive mercury(ii) detection based on dithiothreitol functionalized copper nanocluster/carbon nitride nanocomposites

Huitao Liu; Xueqing Gao; Xuming Zhuang; Chunyuan Tian; Zhenguang Wang; Yanxiu Li; Andrey L Rogach

doi:10.1039/c9an00667b

A specific electrochemiluminescence sensor for selective and ultra-sensitive mercury(ii) detection based on dithiothreitol functionalized copper nanocluster/carbon nitride nanocomposites

Analyst. 2019 Jul 21;144(14):4425-4431. doi: 10.1039/c9an00667b. Epub 2019 Jun 19.

Authors

Huitao Liu¹, Xueqing Gao¹, Xuming Zhuang², Chunyuan Tian¹, Zhenguang Wang³, Yanxiu Li⁴, Andrey L Rogach⁵

Affiliations

¹ College of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, China. xmzhuang@iccas.ac.cn.
² College of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, China. xmzhuang@iccas.ac.cn and Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP), City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR.
³ College of Chemistry and Environmental Science, Hebei University, Baoding 071002, China. wzg583@163.com.
⁴ Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP), City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR.
⁵ Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP), City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR and Shenzhen Research Institute, City University of Hong Kong, Shenzhen, 518057, China.

PMID: 31215573
DOI: 10.1039/c9an00667b

Abstract

Electrochemiluminescence (ECL) sensors are useful for the detection of heavy metal pollutants, in particular mercury(ii) ions, in water samples. We demonstrate the superior sensing performance of Hg²⁺ using a nanocomposite material based on carbon nitride nanosheets (CNNSs) and copper nanoclusters functionalized by dithiothreitol, which not only stabilizes the clusters, but also improves the sensitivity of Hg²⁺ detection. The ECL mechanism is related to the reaction of the nanocomposite with K₂S₂O₈ in the electrochemical system, while the presence of Hg²⁺ leads to quenching of its excited state, and the suppression of the formation of anion-radicals. The Hg(ii) sensor presented here is cheap and fast, and shows high selectivity for the detection of Hg²⁺ on the background of other mono-, di-, and trivalent ions, with a linear range of 0.5-10 nM and the detection limit as low as 0.01 nM.