Solution molarity dependent structural and optical properties of CdO nanostructured thin films

Cadmium oxide (CdO) thin films were prepared on soda lime glasses using sol-gel spin coating method. The optimized annealing temperature of the samples was determined to be 400 degrees C. The structural and optical properties of the films were examined depending on the solution molarity. X-ray diffraction (XRD) patterns confirming that CdO has a cubic crystal structure reveal that the crystallite size gradually increases with increasing solution molaritiy. It is concluded that the molarity of Cd2+ precursor solution does not affect crystallinity. The surface morphology of the CdO thin films was conducted by the solution molarity. The molarity also has an impact on some optical parameters such as extinction coefficient, volume/surface energy loss and refractive index. The band gap obtained form the photoluminescence (PL) measurements of CdO with 0.5 M is in agreement with that of optical absorption spectra.