Chinese Journal of Applied Chemistry ›› 2017, Vol. 34 ›› Issue (3): 291-299.DOI: 10.11944/j.issn.1000-0518.2017.03.160213

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Aqueous Synthesis of Thiol-functionalized Polyvinylalcohol/CdS Quantum Dots Nanocomposite at Low Temperature for Detection of Trace Cu2+ in Water

GUAN Xiaolina*(),JIA Tianminga,QIN Yuxina,ZHANG Donghaia,ZHANG Yanga,FAN Hongtinga,WEI Qiangbinga,LAI Shoujunb   

  1. aKey Laboratory of Eco-Environment-Related Polymer Materials,Ministry of Education
    Key Laboratory of Polymer Materials Ministry of Gansu Province,College of Chemistry and Chemical Engineering,Northwest Normal University,Lanzhou 730070,China
    bSchool of Chemical Engineering,Lanzhou University of Arts and Science,Lanzhou 730000,China
  • Received:2016-05-23 Accepted:2016-07-14 Published:2017-02-27 Online:2017-02-27
  • Contact: GUAN Xiaolin
  • Supported by:
    Supported by the National Natural Science Foundation of China(No.51363019, No.21504070), Specialized Research Fund for the Doctoral Program of Higher Education(No.20136203120002)

Abstract:

A high quality PVA/CdS QDs nanocomposites modified by thiol-functionalized polyvinylalcohol(PVA) was prepared by aqueous synthetic approaches at low temperature. The samples were characterized by infrared spectroscopy(IR), X-ray diffraction(XRD), transmission electron microscopy(TEM), thermogravimetric analysis(TG), photoluminescence spectroscopy(PL) and ultraviolet-visible spectroscopy(UV-Vis). The results show that CdS QDs in the nanocomposites are spherical particles with a cubic crystal structure and a diameter size of about 5 nm. PVA/CdS nanocomposites have good stability, high dispersibility and excellent luminescence properties. Meanwhile, the fluorescent responses of as-prepared PVA/CdS to different metal ions were studied. Based on the fluorescence quenching behavior of PVA/CdS quantum dots, we established a method for the fluorescent detection of Cu2+. When the concentration of Cu2+ is in the range of 1~1000 nmol/L, the fluorescence intensity linearly decreases with the increase of Cu2+ concentration. The linear correlation coefficient is 0.9923 and the detection limit reaches 0.12 nmol/L. The method provides high sensitivity, simplicity of operation and low detection limit, and is successfully applied to the determination of trace copper in the Yellow River samples.

Key words: CdS quantum dots, polyvinylalcohol, nanocomposites, fluorescence sensing, Cu2+