Intensive study on gamma-irradiated PVA/FeCl3/NiO nanocomposites for promising applications: structural, optical and electrical

Abstract

Tuning the optical parameters as well as the electrical conductivity of polymer composites is required to match the needs of optical and/or electrolyte-based energy storage devices. Depending on the choice of filler, the addition of small amounts of inorganic fillers to suitable polymers allows this target to be attained. In the present study, polyvinyl alcohol (PVA)/FeCl₃/xNiO nanocomposites were prepared using the solution cast method. The structural, optical and electrical properties were investigated before and after irradiating the nanocomposites with gamma radiation at two doses, 300 and 400 Gy. Fourier transform infrared analysis confirmed the interaction of NiO with the PVA/FeCl₃ matrix. The nanocomposites show a direct band gap that decreases from 2.47 to 2.25 eV as the NiO content increases from 0% to 7%, while the dc conductivity is increased from 9.15 × 10⁻⁸ to 8.46 × 10⁻⁷ S cm⁻¹. After irradiation by 400 Gy of gamma radiation, the band gap of the PVA/ FeCl₃/7%NiO nanocomposite is increased to 2.33 eV while the dc conductivity decreases to 1.19 × 10⁻⁸ S cm⁻¹. On the other hand, the PVA/FeCl₃ matrix shows low refractive index, 1.134 at 550 nm, which further increases to 1.213 as the NiO content reaches 7 wt%; this is reduced to 1.211 after exposure to 300 Gy of gamma radiation.