Photoluminescence behaviour of Cu doped ZnS Nanoparticles synthesized by wet chemical route method

Cu doped ZnS Nanoparticles in powder form were prepared by wet chemical route method by using thioglycerol as a capping agent. The prepared powder was characterized by using X-ray diffraction (XRD) analysis. The XRD studies indicated that most of the samples are having cubic phase. The absorption spectra, and photoluminescence behaviour of bulk ZnS, nano ZnS and Cu doped ZnS have been studied. Absorption spectra of bulk ZnS and nano ZnS is present around 315 nm no shifting in wave length was observed for both. After doping of Cu ion the absorption wavelength shifted towards the lower wave length around 290 nm, this blue shift in the absorption edge is a measure of increased band gap. Photoluminescence spectra of pure and doped ZnS were recorded under 256 nm. The emission spectrum of pure ZnS has a blue emission band centred at 440 nm. After doping with Cu ion the luminescence centers were transferred to impurity ions. The emission peak of the Cu doped samples is centered at 510 nm. The PL intensity of doped ZnS samples increases in comparison to pure ZnS. Keyword: ZnS, Cu doped ZnS, absorption spectrum, thioglycerol luminescence spectrum.