Hydrophilic AgInZnS quantum dots as a fluorescent turn-on probe for Cd2+ detection

JOURNAL OF ALLOYS AND COMPOUNDS

卷:864

Article

Liu, Yongfeng^1,2  Tang, Xiaosheng²  Deng, Ming²  Zhu, Tao²  Edman, Ludvig¹  Wang, Jia¹ 

[1] Umea Univ, Dept Phys, Organ Photon & Elect Grp, SE-90187 Umea, Sweden

[2] Chongqing Univ, Coll Optoelect Engn, Key Lab Optoelect Technol & Syst, Educ Minist China, Chongqing 400044, Peoples R China

关键词: AgInZnS;    Quantum dots;    Fluorescence;    Probe;    Cd2+ detection;    Defect passivation;   

DOI  :  10.1016/j.jallcom.2020.158109

来源: Elsevier

【 摘 要 】

Quantum dots (QDs) are intensively studied and developed for the detection of toxic heavy metal ions, notably Cd2+. However, a severe drawback is that the probing QDs themselves often are based on highly toxic elements, such as Pb or Cd. Here, we report on a one-step aqueous synthesis of more benign and hydrophilic AgInZnS QDs using 3-mercaptopropionic acid as a ligand with a high photoluminescence quantum yield of up to 41%, which were successfully employed as a fluorescent probe with a turn-on mode for detection of Cd2+ in aqueous solutions. Specifically, we determine that the effective detection range of Cd(2+ )in aqueous solution is 0.1-290 mu M, with the lower limit of detection being 37.8 nM. We further establish that the excellent turn-on detection of Cd2+ is due to that surface defects on the AgInZnS QDs are effectively passivated by the Cd2+, as verified by a prolonged fluorescent lifetime and an increased photoluminescence quantum yield. We finally demonstrate that the AgInZnS QD probe is capable of detecting Cd2+ in lake water samples, and that it meets the WHO standard. (C) 2020 The Authors. Published by Elsevier B.V.

【 授权许可】

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