IJSTE - International Journal of Science Technology & Engineering | Volume 2 | Issue 11 | May 2016 ISSN (online): 2349-784X All rights reserved by www.ijste.org 216 Synthesis and Luminescence Properties of Ni Doped ZnS Nanoparticles B. Hariprasad Reddy G. S. Harish Research Scholar Research Scholar Department of Physics Department of Physics Sri Venkateswara University, Tirupati, 517502, India. Sri Venkateswara University, Tirupati, 517502, India. P. Sreedhara Reddy Professor Department of Physics Sri Venkateswara University, Tirupati, 517502, India. Abstract In this paper we discussed cost effective chemical co-precipitation method for preparing water soluble Ni doped ZnS nanoparticles and studied the effect of dopant concentration on the structural, morphological, compositional and photo luminescence properties using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX) and photo luminescence studies. Broadened XRD peaks confirmed the formation of nano-sized ZnS: Ni nanoparticles with cubic structure at different capping agent concentrations. SEM and EDAX analysis showed surface morphology and effective elemental composition of prepared nanoparticles. The Raman peak observed at 344 cm-1 can be assigned as the LO mode of cubic ZnS. Ni doped ZnS nanoparticles and showed broad emission ranging from 440-520 nm. The Photo Luminescence intensity of ZnS: Ni Nanoparticles is enhanced by the incorporation of Ni ions. Keywords: chemical co-precipitation, nanoparticles, photoluminescence, scanning electron microscopy, X-ray diffraction ________________________________________________________________________________________________________ I. INTRODUCTION The nano-sized materials have found many novel applications and are attracted great interest due to enhanced mechanical, optical, opto-electronic and magnetic properties of nanocomposite. II–VI semiconducting nanoparticles have attracted great interest due to their unique structural, optical and electronic properties which arise due to their large surface to volume ratio [1-5]. ZnS nanoparticles doped with Ni2+ have been obtained by chemical co-precipitation from homogeneous solutions of zinc and nickel salt compounds with S2- as precipitating anion formed by decomposition of sodium sulfide. Average particle size and structural analysis of the doped and pure ZnS nanoparticles were observed by X-ray diffraction analysis. Enhanced luminescence properties were observed in photoluminescence spectra of ZnS nanoparticles doped with Ni2+. Composition analysis and surface morphology information were obtained from EDS and SEM analysis respectively. Raman studies showed the absence of impurities and effective doping of Ni2+ ions into ZnS. II. EXPERIMENTAL AND CHARACTERIZATION TECHNIQUES All the chemicals were of analytical reagent grade and were used without any further purification. The samples were prepared by chemical co-precipitation method using pure zinc acetate, nickel chloride and sodium sulfide. Appropriate amounts of Zn(ac)2 and NiCl2. 6H2O were dissolved in 50ml distilled water. To this solution, 50ml of sodium sulfide solution is added drop wise under constant stirring until to get fine precipitate of Ni doped ZnS nanoparticles. After the completion of the reaction, products were collected and thoroughly washed for several times with distilled water and ethanol, Ni doped ZnS nanoparticles were subjected to various characterization studies. The X-ray diffraction patterns of the samples were collected on a Seifert 3003 TT X- Ray diffractometer with the Cu Kα radiation (λ=1.5405A°). Elemental composition of the prepared samples were analyzed through EDS using Oxford Inca Penta FeTX3 EDS instrument attached to Carl Zeiss EVO MA 15 Scanning Electron Microscope. Photoluminescence spectra of the present Nano powders have been recorded using a Horiba-Fluorolog-3 (Model FL3-22) spectrofluorometric at room temperature (300 K). Raman Spectroscopic studies of the as prepared samples were carried out using LabRam HR800 Raman Spectrometer.