Films of pure and doped Polyvinyl alcohol (PVA) with different concentration of Nickel Chloride (NiCl2) were prepared using the casting technique, in order to investigate the effect of NiCl2 additions on the optical properties of PVA host. The dispersion studies of pure PVA film and PVA films doped with NiCl2 were studied using complex refractive index in the wavelength range 190-1100 nm. The absorption spectral analysis showed that the optical energy band is due to the direct and indirect allowed optical transitions. The optical energy band gap Egopt of the films decreases with increasing NiCl2 contents, while the Urbach energy ∆Et called the width of localized states in the optical band gap decreases from 0.7414 to 0.1891 eV. The reductions of optical energy band gap were observed for all samples after annealing at temperatures 70oC for three hours.

Solid polymer electrolyte films based on polymer blends of poly(vinyl alcohol) (PVA) and poly(ethylene oxide) (PEO), with different concentration of copper (II) chloride (CuCl 2 ) were prepared using casting technique. Optical studies were performed using Fourier transform infrared (FT-IR) and Ultraviolet-visible (UV-Vis) spectroscopy. The optical properties of these films were varied by varying CuCl 2 concentration. The results show the absorption edge for electrolyte samples shifts toward a lower energy region by increasing the salt concentration, leading to the band gap reduction. The band gap energy data showed that the incorporation of CuCl 2 into the polymeric system causes charge transfer complexes in the blend polymer, which lead to increase in the electrical conductivity, by providing additional charges in the lattice. The PVA/PEO/CuCl 2 solid polymer electrolyte films exhibit good UV shielding properties in the wavelength range from 190 to 400 nm.

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