Department of Chemical Sciences, University of Johannesburg, 2028, Doornfontein, Johannesburg, South Africa.
Center for Nanomaterials Science Research, University of Johannesburg, 2028, Doornfontein, Johannesburg, South Africa.
J Fluoresc. 2022 Sep;32(5):1769-1777. doi: 10.1007/s10895-022-02988-1. Epub 2022 Jun 9.
Quantum dots (QDs) have attracted much attention over the past decades due to their outstanding properties. However, obtaining QDs with excellent photoluminescence and quantum yields (QYs) from their aqueous synthesis is still a big concern. We herein present a green and facile synthesis of AgInS (AIS) QDs and AgInS-ZnS (AIS-ZnS) core-shell QDs using a combination of two capping agents (glutathione and sodium citrate). The temporal evolution of the optical properties is investigated by varying the reaction time and pH of the solution. The results show that the fluorescence intensity of the QDs increases as the reaction time increase, while the emission position blue-shift as the pH of the solution increase. An outstanding photoluminescence quantum yield (PLQY) of 90% is obtained at optimized synthetic conditions. The Fourier transform Infrared studies confirm efficient passivation of the QDs by the capping agents. The XRD analysis reveals that all the materials crystallize in the tetragonal crystalline phase, while the TEM micrographs of AIS-ZnS QDs reveal a spherical shape. The EDS analysis confirms the presence of Silver, Indium, Sulphide, and Zinc elements. The reported synthetic route is facile and eco-friendly.
量子点 (QDs) 由于其出色的性能在过去几十年中引起了广泛关注。然而，从其水相合成中获得具有优异光致发光和量子产率 (QY) 的 QDs 仍然是一个大问题。我们在此提出了一种使用两种封端剂（谷胱甘肽和柠檬酸钠）的绿色简便的 AgInS (AIS) QDs 和 AgInS-ZnS (AIS-ZnS) 核壳 QDs 的合成方法。通过改变反应时间和溶液的 pH 值来研究光学性质的时间演化。结果表明，随着反应时间的增加，QDs 的荧光强度增加，而随着溶液 pH 值的增加，发射位置蓝移。在优化的合成条件下，获得了 90%的出色光致发光量子产率 (PLQY)。傅里叶变换红外研究证实了封端剂对 QDs 的有效钝化。XRD 分析表明所有材料都结晶为四方晶相，而 AIS-ZnS QDs 的 TEM 显微照片显示出球形。EDS 分析证实存在银、铟、硫和锌元素。所报道的合成路线简单且环保。
