Comparative investigation of some selected properties of Mn3O4/PbS and CuO/PbS composites thin films

In this paper, a comparative study of Mn3O4/PbS and CuO/PbS composites deposited by chemical bath deposition (CBD) method has been made using x-ray diffraction (XRD), Scanning electron microscope (SEM), Rutherford backscattering (RBS), UV-vis spectroscopy and four point probe techniques. Structure of both composites were observed by XRD technique. The crystallite size for Mn3O4/PbS and CuO/PbS polycrystalline films were found to be 34.86 nm and 19.14 nm respectively. The surface morphology of both composites were observed by SEM technique. Mn3O4/PbS films showed non-uniform irregular spherical particles spread across the substrate surface, whereas CuO/PbS thin films showed uniform grains with dense structure which are well covered to the substrate with rod like structure. Both films have high absorbance exhibiting a maximum in the UV region. The direct band gaps of 3.90 eV and 3.95 eV were observed for Mn3O4/PbS and CuO/PbS films respectively. The wide band gap values are in the range suitable for use as window materials in solar cell fabrication and high frequency applications.