Mechano-chemical synthesis and optical properties of ZnS nanoparticles

Abstract

In the present work, we report the synthesis and optical properties of ZnS nanoparticles produced by the mechano-chemical route. We used zinc acetate and sodium sulphide as source materials in a high energy planetary ball mill at rotation speed of 300rpm and vial rotation speed of 600rpm with ball to powder (BPR or charge ratio CR) 5:1 for 30 and 90min. The milled powders were washed with methanol to remove impurity and dried at 300°C for 1h. The prepared nanoparticles have been characterized using X-ray diffraction (XRD), Field emission scanning electron microscope (FESEM), UV–vis–NIR spectrophotometer and Fluorescence spectroscopy. The crystallite size of the synthesized ZnS nanoparticles is found to be in the range 7–8nm which was calculated using Debye–Scherer's formula. The value of optical band gap has been found to be in the range 3.80–4.15eV. Room temperature photoluminescence (PL) spectrum of ZnS samples exhibit a blue emission peaked at 466nm under UV excitation.