Effect of excess oxygen content within different nano-oxide additives on the structural and optical properties of PVA/PEG blend

Different nano-oxides (Cr2O3, NiO, Co3O4) were added to polyvinyl alcohol/polyethylene glycol (70/30 wt%) blend. Rietveld profile analysis method was used to investigate the structure and microstructure characteristics of nano-oxide fillers. The effect of different nano-oxide fillers on the optical transparencies of the blend samples is confirmed. Co3O4 nano-oxide showed a higher uniform distribution within blends among other oxides. The variation of the absorption, the transmittance, the extinction coefficient, the refractive index and the energy gap (direct and indirect) of different blends based on different oxide fillers was examined by UV–Vis spectrophotometry technique. A single-term Sellmeier Oscillator approximation model was used to investigate the effect of excess oxygen atoms of the added nano-oxide fillers on the strength of the inter-band optical transitions, average excitation energy, average inter-band oscillator wavelength, the long-wavelength refractive index and the average oscillator strength. The effect of doping on the dielectric constant (real and imaginary) and optical conductivity of different blends behavior was investigated in detail as well.