Chinese Journal of Applied Chemistry ›› 2020, Vol. 37 ›› Issue (5): 587-594.DOI: 10.11944/j.issn.1000-0518.2020.05.190312

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Synthesis of 2-Mercaptobenzimidazole-Functionalized Water-Soluble Copper Nanoclusters and Their Application to the Determination of Ag+

CAI Zhifenga,CHEN Siyinga,PANG Shulina,SONG Shuanga,JIA Kanga,MAO Yujina,TIAN Fanga*(),ZHANG Caifengab*()   

  1. aDepartment of Chemistry,Taiyuan Normal University,Jinzhong,Shanxi 030619,China
    bHumic Acid Engineering and Technology Research Center of Shanxi Province,Taiyuan Normal University,Jinzhong,Shanxi 030619,China
  • Received:2019-11-20 Accepted:2020-02-20 Published:2020-05-01 Online:2020-04-29
  • Contact: TIAN Fang,ZHANG Caifeng
  • Supported by:
    Supported by the Shanxi Provincial Applied Fundamental Research Fund Project(No.201801D121257)


We reported a direct one-pot approach, employing 2-mercaptobenzimidazole as a protective agent, polyvinyl pyrrolidone as a stabilizer and hydrazine hydrate as a reducing agent, for rapid preparation of highly stable, strong fluorescent, large Stokes shift fluorescent copper nanoclusters (Cu NCs) from Cu(NO3)2 in aqueous solution at room temperature. Meanwhile, we studied the possibility of the Cu NCs to detect silver ion in water samples. The structure of Cu NCs was characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The optical performance was studied using fluorescence spectroscopy and UV-visible absorption spectroscopy. The as-prepared Cu NCs exhibit a fluorescence emission at 559 nm, and show colorless and orange fluorescence under sunlight and UV light irradiation, respectively. The Cu NCs were highly dispersed with the size of 2~3 nm. In addition, it exhibits good water solubility, excellent photostability and high stability toward high concentration of sodium chloride. Under optimal reaction conditions, the Cu NCs can be used for the highly sensitive and selective detection of silver ions (Ag+) in aqueous solution. The fluorescence intensity quenches linearly within the range of 1 to 40 μmol/L with high sensitivity (LOD=0.5 μmol/L, S/N=3) and this sensing system has been successfully applied for environmental water sample analysis.

Key words: copper nanoclusters, 2-mercaptobenzimidazole, silver ions, quenching