Four-phases characterization of synthesised CeO2 thin films: Effect of molarity on structural, optical, physical properties and gamma-ray attenuation parameters

A group of novel CeO2 thin films were synthesised using ultrasonic spray pyrolysis process. The composition ratios of these films were modified to investigate changes in their optical, surface, electrical, and structural characteristics. Absorbance spectra in the range 300-900 nm was acquired. Transmittance in the visible area was determined to be 50%. The optical band gap was reported to vary between 3.38 and 3.52eV using absorbance spectra. X-ray diffraction was used to analyse the films' structure, while atomic force microscopy was used to determine the surface roughness values. Spectroscopic ellipsometry and the Cauchy-Urbach model were used to calculate the thicknesses. Electrical resistivity values were determined using a four-probe system. CeO2 thin film X-ray diffraction patterns validated the polycrystalline cubic fluorite structure. According to the data, the deposited films expand preferentially in the (2 0 0) direction. The films were found to have a high resistivity of 10(6) Omega cm. We also evaluated the nuclear radiation shielding properties of CeO2 thin films in the 0.015-15 MeV photon energy range. The results indicated that CeO2 thin film exhibits promising half value layers of 0.00169 cm, 0.14055 cm, 1.62665 cm, and 2.30273 cm, respectively, for 0.015 MeV, 0.15 MeV, 1 MeV, and 15 MeV CeO2 films have been determined to be worth working on and may be promising materials for optoelectronic and nuclear security applications.