Improvement Structural and Optical Properties of ZnO/ PVA Nanocomposites

The structural and optical properties of polyvinyl alcohol (PVA) doped with different concentrations (0, 0.15, 0.5, 1, 2, 2.5, and 3 wt %) of ZnO nanoparticles were studied. ZnO nanoparticles were prepared by the solgel methode, and nanocomposite films were prepared using the solution casting methode. Nanocomposites films were characterized by X-ray diffraction (XRD), Fourier Transformer Infrared (FTIR). The optical properties and optical constants of ZnO/ PVA nanocomposite films have been investigated by means of transmittance and reflectance spectra. The optical band gap Eg was determined and the optical absorption spectra showed that the absorption mechanism is a direct transition. The refractive index (n), extinction coefficient (k) and dielectric constant of the films were determined. We have applying Wemple – Didomenico single oscillator model to calculate the dispersion of the refractive index.. The nanocomposite ZnO/ PVA (3% wt) shows the lower optical band gap value and the higher optical conductivity as compared to other concentration of ZnO.