Effect of gamma radiation on the optical and color properties of Makrolon/Pocan/ZnS-NiO nanocomposite films

Abstract

Makrolon/Pocan is a polymer blend of amorphous polycarbonate (PC) and semicrystalline polybutylene terephthalate (PBT). We fabricate a nanocomposite (NC) of PC/PBT polymer blend, Zinc sulfide (ZnS) and Nickel oxide (NiO) nanoparticles by the sol–gel and ex-situ casting processes. We trust that this study is novel in the area of the impact of γ radiation on this NC. The Rietveld modification of XRD records indicates that both the prepared ZnS and NiO have a nano-nature of an average particle size of 4 and 18 nm, respectively. Samples of the PC-PBT/ZnS-NiO NC films are irradiated with several γ doses (10 − 100 kGy). We investigate the resulting outcome of the γ irradiation on the linear and non linear optical behavior of the NC films, using ultraviolet spectroscopy (UVs) and the International Commission on Illumination (CIE) color changes technique. Upon increasing the γ dose up to 100 kGy, the maximum dose used, both direct and indirect bandgaps decreased. The Urbach energy exhibits a reverse trend. We attribute this to the dominance of chain crosslinks that damaged the ordered configuration and thus increased the amorphous phase. This suggests that the γ radiation can facilitate the spreading of the nanoparticles within the composite matrix suggesting an extra compacted structure of the NC samples. Also, we detect the nature of microelectronic transitions, using the optical dielectric loss (ε”), and found that the PC-PBT/ZnS-NiO NC films had direct allowed transitions. Moreover, we study the γ-induced modifications in the optical conductivity, dielectric parameters and nonlinear optical parameters. Further, the color changes between the pristine and irradiated films were estimated. The pristine NC film exhibited significant color differences upon γ irradiation. The induced improvements in the optical characters suggest that the γ is a suitable mean that permits the use of PC-PBT /ZnS-NiO NC in the optoelectronic devices.