Nanocomposites (NC) of amorphous polycarbonate (PC) and zinc sulfide (ZnS) and cerium oxide (CeO2) nanoparticles (NP) were synthesized. The synthesized CeO2 and ZnS had a nanonature of average particle size 22 and 18 nm, respectively. Samples of the PC/ZnS-CeO2 NC films were irradiated with several γ doses (10-120 kGy). The resultant outcome of the γ ray irradiation on the optical behavior of the NC films was studied using UV-vis spectroscopy. Upon raising the dose up to 120 kGy, the direct bandgap decreased from 5.23 to 4.51 eV. The Urbach energy showed an opposite tendency; it increased from 0.38 to 0.92 eV. This can be attributed to the dominance of chain crosslinks. Also, the optical dielectric loss (ε”) aided in detecting the nature of the microelectronic transitions. It was found that the PC/ZnS-CeO2 NC films had direct allowed transitions. Additionally, the γ ray induced alterations in the light absorbance, extinction coefficient, refractive index and optical conductivity of the PC/ZnS-CeO2 NC films were studied. Moreover, the optical color changes between the pristine and the irradiated films were determined. The pristine NC film was uncolored. It showed significant color alterations when irradiated with γ ray doses up to 120 kGy.
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