Synthesis, structural, and optical properties of core/shell ZnS:Fe/ZnS nanocrystals

Abstract

Abstract ZnS:Fe/ZnS core/shell nanocrystals (NCs) were synthesized by a simple liquid‐solid‐solution (LSS) method and the influence of ZnS shell thickness on the optical properties of ZnS:Fe/ZnS NCs was investigated. The crystalline and optical properties of ZnS:Fe/ZnS core/shell NCs were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy, UV–Visible spectrometer and FT‐IR spectrometer, respectively. It was found that the ZnS:Fe/ZnS core/shell NCs are highly crystalline and show zincblende structure with an average particle size of about 7 nm. The lattice constants of the ZnS:Fe/ZnS NCs decrease slightly by the introduction of Fe, and the Fe dopants were well doped into the ZnS:Fe/ZnS NCs, as confirmed by XPS. Compared to the pure ZnS:Fe NCs, the ZnS:Fe/ZnS core/shell NCs exhibited significantly enhanced luminescence properties. A red‐shift can be observed in the absorption and PL spectra as the ZnS shells thickened.