Structure and Photoluminescence Properties of Zinc Sulfide Nanoparticles Prepared in a Clay Suspension

Zinc sulfide nanoarticles (ZnS NPs) were prepared under several precursor concentration conditions in Laponite XLG suspension as clay stabilizer to prevent the aggregation of ZnS NPs and to enhance their photoluminescence (PL). We measured their properties such as PL, UV-vis absorption, X-ray diffraction, and the particle image by transmission electron microscopy. The results of the measurements showed that ZnS NPs prepared in the presence of the clay particles were monocrystalline particles, since the dispersed Laponite XLG clay particles had a stabilizing effect on ZnS NPs. ZnS NPs prepared without clay were the aggregated particles of multicrystalline particle. When the precursor concentration of ZnS NPs increased, the particle diameter of ZnS NPs increased. These results agreed with von Weimarn's law. PL originating from the defect level on the ZnS NPs surface was observed. The PL intensity was enhanced due to the increase of the particle surface area, as the clay particles existed or the particle diameter of ZnS NPs decreased.