Structural and optical studies on nickel oxide thin film prepared by nebulizer spray technique

In the present work, nickel oxide thin film has been deposited on glass substrates at temperature 400 °C by simple and inexpensive nebulizer spray technique. The effect of the volume of sprayed solution on structural and optical properties of the films were investigated using X-ray diffractometer, UV–Vis–NIR spectrometer, photoluminescence, Raman spectrum and linear four probe resistivity measurement, respectively. It is found that increase in the sprayed volume of solution with 0.3 M leads to increase in the film thickness. XRD studies indicated cubic structure and the crystallites are preferentially oriented along the [1 1 1] direction. It is also found that as the sprayed volume of the solution increases the transmittance decreases, consequently the band edge shifted from lower wavelength to higher wavelength and the band-gap energy wanes from 3.64 eV to 3.13 eV. From PL spectra, the sample shows sharp and strong UV emission around 376 nm corresponding to the near bandedge emission of NiO under excitation of 275 nm.