A Study of Synthesis and Characterization of Transition Metals Doped Zinc Sulfide Nanoparticles

Abstract

The transition metals (Co, Fe, and Cr) doped zinc sulfide nanoparticles were newlineprepared at room temperature using the co-precipitation method. The effect of newlinedifferent dopant concentrations on the structural, morphological, compositional, newlineoptical, and electrical properties of Co, Fe, and Cr doped ZnS nanoparticles has been newlinestudied and discussed. newlineX-ray diffraction studies of all samples confirmed that the prepared newlinenanoparticles have a single-phase cubic crystal structure of ZnS and that transition newlinemetal ions are entered into the ZnS lattice. The X-ray diffraction peaks for all the newlinesamples appeared to be broad indicating the formation of nano-sized particles. The newlinereduction in lattice constant is observed with an increase in dopant concentration in newlineZnS: Co and ZnS: Fe nanoparticles whereas variation in lattice constant is observed in newlineZnS: Cr nanoparticles. The increase in dislocation density with increasing dopant newlineconcentration of all samples clearly shows a reduction in crystallinity of ZnS newlinenanoparticles. newlineThe FE-SEM images of all samples demonstrated that agglomerated grains newlinehave a nearly spherical shape and grain distribution is non-uniform. The particle newlineagglomeration increased in case of ZnS: Co nanoparticles whereas it decreases in newlineZnS: Fe and ZnS: Cr nanoparticles as doping concentration increased. newlineThe EDAX spectra confirmed the presence of Zn and S in undoped ZnS newlinesample whereas transition metal elements are present in doped ZnS nanoparticles. The newlinepeaks of other elements were not observed in spectra that confirmed prepared samples newlineare pure. The EDX spectra study also confirmed that the percentage of atomic weight newlineof Co, Fe and Cr increased with increasing doping concentration, indicating that the newlinetransition metal ions were successfully introduced into the ZnS host matrix. newlineOptical studies showed that the absorption peaks are observed to be red shifted newlinein ZnS: Co and ZnS: Fe nanoparticles and bandgap energy found to be decrease with newlinean increase in dopant concentration whereas absorption peaks are blue shifted in ZnS