Absence of photocatalytic activity in the presence of the photoluminescence property of Mn-ZnS nanoparticles prepared by a facile wet chemical method at room temperature

Mn-doped ZnS nanoparticles (NPs) were prepared with dopants at various concentrations using a facile, simple and inexpensive wet chemical method at room temperature. The physicochemical properties of NPs were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible absorption spectroscopy (UV-vis) and photoluminescence (a). XRD analysis confirmed formation of ZnS with zinc blende structure and average crystallite size of about 2 nm. TEM analysis revealed formation of hyperfine NPs with rather good uniformity. The room temperature photoluminescence (PL) spectrum of ZnS:Mn2+ exhibited an orange-red emission around 600 nm. The maximum PL intensity was observed for 7.5% Mn doped ZnS. The photocatalytic performance of ZnS:Mn2+ was successfully demonstrated for degradation of three different model dyes (i.e. Rhodimine B (Rh. B), Bromocresol Green (BCG) and Bromochlorophenol Blue (BCB)). The results revealed that not only was there a remarkable difference in photocatalytic performance of Mn doped ZnS for all three different dyes at different dopant concentrations but also photocatalytic activity was decreased by Mn doping. (C) 2013 Elsevier Ltd. All rights reserved.