Influencing of Substrates Types on the Optical Properties of Nickel Oxide Films Deposited by Silar Method

In this study, some optical properties of nickel oxide (NiO) films deposited on different glass substrates (ITO, FTO, glass) were characterized by the successive ionic layer adsorption and reaction (SILAR) method. All films were determined to form in the cubic phase of NiO according to the Joint Committee on Powder Diffraction Standards (JCPDS:01-073-1519) card. Some optical properties such as the energy gap were measured as the values of the direct optical Energy gap changed in the range (3.81-3.88 eV). The results showed that the transmittance values in the visible range of the samples gradually increased with wavelength (from 15% to 54%), with a clear superiority in the transmittance values of the films deposited on ITO substrates. Similar to the transmittance and absorbance values of the samples, the films deposited on (glass) showed linear behavior, in contrast to the rest of the samples deposited on FTO and ITO substrates, which showed exponential behavior with higher transmittance. Similar light absorption behavior was observed across all samples, with a proportional decrease in absorption values with increasing wavelength. The films had identical results to previous studies, indicating the reliability of the SILAR method in film preparation and characterization. The maximum absorption peaks are limited to the short wavelength range (300-350 nm).