Electrodeposition of cobalt oxide thin films for potential applications
محورهای موضوعی : Journal of Theoretical and Applied PhysicsSandra Augustine 1 , Azubike Ekpunobi 2 , Diemiruaye Jeroh 3
1 - Department of Physics and Industrial Physics, Nnamdi Azikiwe University, Awka, Nigeria.
2 - Department of Physics and Industrial Physics, Nnamdi Azikiwe University, Awka, Nigeria.
3 - Department of Physics and Industrial Physics, Nnamdi Azikiwe University, Awka, Nigeria.
کلید واژه: crystalline, band widening, cobalt oxide, blue-shift, molar concentrations,
چکیده مقاله :
Cobalt oxide thin films at varied molar concentrations were prepared by electrodeposition technique. Ultraviolet-Visible (UV/VIS) analysis conducted on the grown films revealed blue shift in the absorption edge at increased molar concentrations, which is a consequence of band gap widening. The band gap values (3.65 eV to 3.85 eV) in this research are greater than the value (2.4 eV) for the bulk phase of cobalt oxide. This increase in band gap can be likened to higher concentration effect and quantum-size phenomenon. Scanning Electron Microscopy (SEM) analysis indicated a porous nature for the material, suggesting its ability in absorbing ultraviolet (UV) radiation, thus confirming its use as an absorber material for solar cells fabrication. Energy Dispersive X-ray (EDX) study confirmed the growth of cobalt oxide. X-ray diffraction (XRD) analysis confirms the crystalline nature of the films with grain sizes within the range of 0.7 nm to 1 nm for varied molar concentrations. Electrical studies reveal a linear relationship of resistivity values with molar concentrations, while the conductivity values reveal inverse relationship with molar concentration.