The Structural and Optical Properties of Cobalt dioxide (CoO2 )Thin Films deposited via (SCSP) Technique for photovoltaic applications

Abstract

The research included the preparation and then studying the structural and optical properties of the cobalt dioxide (CoO2)films. The latter films were prepared using a semi-computerized spray pyrolysis technique (SCSPT),. The X-ray diffraction gave polycrystalline nature with crystal system trigonal (hexagonal axes), and the Energy Dispersive X-ray spectroscopy (EDX) showed that all films contain the elements (Co and O) indicating formation of (CoO2) films with high purity. FTIR measurements showed of chemical bonds of CoO2 clearly. Scanning Electron Microscopy (SEM ) Showed clearly that the formed thin films under the optimum conditions were homogeneous, dense and compact, and Atomic Force Microscopy(AFM) results showed that the topography of the film surface where surface roughness was found to be 7.91 nm, root mean square was 9.69 nm., and the average granularity diameter was 78.00 nm. The optical properties (absorbance, absorption coefficient, extinction coefficient, refractive index, optical Conductivity, the real ε_(1 ) and imaginary ε_2 part of the dielectric constant )were decreased with increasing the wavelength, while the transmittance increases with increasing wavelength. The optical energy gap was (1.98eV) and this is a good optical energy gap values for photovoltaic applications.