Structural and optical properties of Ni doped ZnO thin films using sol–gel dip coating technique

Ni-doped zinc oxide (Ni:ZnO) thin films were deposited on glass substrates by sol–gel dip-coating technique with different pH values. The films were characterized structural, morphological, compositional and optical properties respectively. X-ray diffraction revels that all samples have a polycrystalline in nature with hexagonal wurtzite structure. The structural parameters such as crystallite size, dislocation density and micro strain were calculated from XRD studies. Scanning electron microscopy shows irregular grains with average grains size found to be ∼150 nm at 400 °C. Energy dispersive X-ray analysis indicates that the presence of Ni, Zn and O elements with average atomic percentage of Ni:ZnO was 04.19:44.99:50.82 at 400 °C. Optical absorption spectra show that the band gap energy is decreases with the increase in pH values.