Gamma irradiation-induced changes in structural, linear/nonlinear optical, and optoelectrical properties of PVB/BiVO4 nanocomposite for organic electronic devices

Herein, nanocomposite films based on polyvinyl butyral (PVB) and BiVO4 plates were synthesized through solution casting. The present study aims to investigate the impact of varying doses of gamma irradiation (0, 15, 30, 60, and 90 kGy) on the structural, dispersion, linear/nonlinear optical, and optoelectrical properties of PVB/BiVO4 nanocomposite films. The effects of gamma irradiation on various optical characteristics, such as refractive index (n), extinction coefficient (k), and other related parameters, have been observed. The study of dielectric behavior and the derivation of optoelectrical parameters, including high-frequency dielectric constant (ε∞), plasma frequency (ωP), relaxation time (τ), and optical mobility (µopt.), were conducted using the real and imaginary parts of the dielectric constants εr and εi. In addition, the linear optical susceptibility (χ(1)), the third-order nonlinear optical susceptibility (χ(3)), and the nonlinear refractive index (n2) were studied as a function of gamma irradiation doses. Furthermore, the results demonstrate that the average oscillator wavelength (λ0) values, oscillator strength (S0), and optical conductivity (σopt) vary significantly after gamma radiation treatment. Overall, the strong correlations between the linear/nonlinear optical and optoelectrical parameters of the irradiated PVB/BiVO4 nanocomposite films make them suitable for application in flexible organic electronic devices.