Study of optical properties of pure and MoO3-doped polyvinyl alcohol films irradiated with γ-rays

Cast thin films of pure and MoO3-doped polyvinyl alcohol (PVA) have been prepared. The optical transmission spectra in ultraviolet to near-infrared regions are investigated before and after irradiation by different doses of γ-rays in the range 102 to 107 Gy. The analysis of transmission spectra showed that the intensity of the bands is remarkably affected by both dopant concentration and γ-irradiation doses. The disappearance of the transmission band at 265 nm in 1.0 wt% and 2.0 wt% MoO3 is attributed to the structural change due to dopant. It was found that doping with molybdenum oxide results in an additional band at 600 nm. The optical energy gap and band tail of pure and MoO3-doped PVA samples at different γ-doses are estimated.