Influence of Mn Doping on the Microstructure and Optical Properties of Zns Nanocrystals

摘要

ZnS nanoparticles with Mn~(2+) doping (0-2.5%) were prepared through a simple chemical method. The nanostructures of the prepared undoped ZnS and Mn~(2+)-doped ZnS:Mn nanoparticles had been characterized by X-ray power diffraction (XRD), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), photoluminescence spectra (PL) and UV–vis absorption spectra. The mean size of the particles was found to be approximately 3-5 nm through XRD measurements, TEM and the UV–vis absorption spectra. It was found that the Mn~(2+) ~4T_1→~6A_1 emission intensity of ZnS:Mn nanoparticles was significantly enhanced with the increase of Mn~(2+) concentration, which arrived a maximum value when Mn~(2+) initial doping concentration was 1.5%. Continue increasing the Mn~(2+) concentration, namely more than 1.5%, the Mn~(2+) ~4T_1→~6A_1 emission intensity became weakened. And the resultant ZnS:Mn nanoparticles exhibited high efficiency for degrading methylene blue under UV light irradiation.