Mechanochemical synthesis, characterization and optical properties of zinc sulphide nanoparticles

Abstract

Nanosized zinc sulphide (ZnS) was synthesized by the mechanochemical route using zinc acetate and sodium sulphide as source materials in a high energy planetary ball mill (Retsch PM 400/2) for 30–90 min at rotation speed of 300 rpm and vial rotation speed of 600 rpm with ball to powder ratio 5:1. The milled powder was washed with methanol to remove impurity and heat treated at 100–400 °C. ZnS nanoparticles then characterized by using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), UV–Vis–NIR spectrophotometer and fluorescence spectrophotometer. The crystallite size of the synthesized ZnS nanoparticles is found to be in 3–9 nm range. FESEM morphology shows the formation of nanostructure of ZnS samples. The value of optical band gap has been found to be in the range 3.87–4.66 eV. Room temperature photoluminescence spectrum of ZnS samples exhibit a blue emission peaked at 466 nm under UV excitation.