Optimization and Characterization of Spray Pyrolysis Synthesized Nanostructured Nickel Oxide Films

Abstract

Using spray pyrolysis technique, crystalline nanostructured Nickel Oxide (NiO) films were synthesized on glass substrates with different molarities of hydrated nickel chloride salt precursors solution (NiCl2.6H2O) at various substrate temperatures. Characterizations of synthesized nanostructured NiO films were investigated by using X-Ray Diffractometer (XRD), UV-Visible Spectrophotometer (UV–Vis), and Field-Emission Scanning Electron Microscopy (FESEM) with Energy Dispersive X-ray Spectrometer (EDX). Based on XRD analysis, the molar concentration and substrate temperature of the prepared films were optimized as 0.2 M and 400 °C, respectively. The XRD result showed to the formed cubic polycrystalline structure films with preferred orientation along (111) direction. The UV–Vis spectrophotometry analyzing showed the band gap of NiO films varied from 3.630 eV to 3.85 eV. The surface morphology analysis revealed that the nanoparticles are extra-fine, with an average particle size of 68.838 nm. The stoichiometric elemental composition ratio of NiO was confirmed by EDX analysis. The overall results of this study suggested that the synthesized high quality crystalline nanostructured NiO films would be highly suitable for gas sensing applications.

Keywords

• spray pyrolysis
• nio nanostructure
• molarity
• substrate temperature
• characterization