Structural and optical properties of zinc oxide nanoparticles

Abstract

Nanostructured zinc oxide (ZnO) is synthesized through a novel chemical route using molar solutions of zinc acetate dehydrate, lithium hydroxide and ethanol as starting materials with n-hexane as capping agent. The prepared samples are annealed at higher temperatures, viz. 50°C, 150°C, 300°C and 500°C. The structure and morphology of the samples are studied using X-ray diffraction (XRD) analysis and Transmission Electron Micrscopy (TEM). X ray diffraction (XRD) analysis revealed the synthesized nanoparticles are of hexagonal wurtzite phase. Average particle size of the prepared samples are 9 nm, 12 nm, 25 nm and 45 nm respectively. Besides directly measuring particle size, the morphology of the particles can be observed through TEM analysis. Optical properties are investigated by using uv-visible absorption (uv-vis) and photoluminescence (PL) spectroscopy. UV–vis absorption spectra have been utilized to calculate the band gap. The optical band gap value of the prepared ZnO nanoparticle is found to be 3.36 eV which indicates the presence of blueshift.