Structural and optical study of mixed structure of ZnO(hexagonal)/ZnS(cubic) nanocomposites

ZnO, ZnS and ZnO/ZnS nanocomposites were successfully synthesized by chemical method in an air atmosphere. Water–ethanol matrix was used as solvent. The as-obtained samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–visible (UV–vis) and photoluminescence (PL) spectrophotometer. The results showed that the ZnS nanoparticles are cubic in structure with the size of about 5 nm growed on the surface of the hexagonal ZnO nanocomposites. The optical study of ZnO/ZnS nanocomposites showed an enhanced PL emission in visible region. The photoluminescence property of the ZnO/ZnS core/shell nanocomposites is varied with respect to the shell thicknesses. PL quenching is observed by increasing of shell thickness on ZnO.

Due to complete elimination of surface defect, an enhanced photoluminescence was observed for ZnO/ZnS core–shell nanoparticles.Figure optionsDownload as PowerPoint slideHighlights
► ZnO/ZnS core–shell nanocomposites were synthesized through chemical method in air atmosphere.
► Mixed structure (cubic and hexagonal) was observed.
► An optimum shell (ZnS) thickness was determined.
► A strong blue shift was observed in UV absorption.
► An enhanced PL emission was observed by ZnS coated ZnO nanocomposites.