Low temperature chemical synthesis of ZnS, Mn doped ZnS nanosized particles: Their structural, morphological and photophysical properties

In this paper, we report synthesis of ZnS and Mn doped ZnS nanosized particles by a simple and effective chemical method and their structural, morphological and photophysical properties. XRD and TEM analysis confirmed the formation of nanosized ZnS and Mn doped ZnS particles. The ZnS nanoparticles were found to be of spherical shape with size <5 nm (average) which further decreases with increasing Mn doping concentration. FESEM and AFM analysis were carried out to get an insight of the morphology of the as prepared nanoparticles in thin film form. As revealed by FESEM, the thin films were found to show uniform morphology along with formation of clusters due to agglomeration of the nanosized particles. AFM analysis suggests that the surface roughness of the films reduces with increasing Mn doping percentage in ZnS. UV-Vis and PL analysis were carried out to study the photophysical properties of the ZnS and Mn doped ZnS nanostructures.The UV-Vis spectra show the presence of blue shift in the absorption peak along with an increase in band gap attributable to the quantum confinement effect. This blue shift increases as the Mn doping percentage in ZnS increases (0.06-0.17 eV). The PL spectroscopy confirms the presence of yellow/red peak arising from the doping of Mn in ZnS nanoparticles.