Role of Cu/ZnO nanostructures doping on the optical behavior of polyvinyl alcohol/polyvinyl pyrrolidone/graphene composites for optoelectronic applications

Abstract The linear/non-linear optical and dielectric performance of PVA/PVP/graphene composites were enhanced by doping with Cu/ZnO (ZCO) nanoparticles (NPs) for optoelectronic applications. Bare and ZCO polymeric nanocomposites (PNCs) blends were fabricated by the casting method. The structure of the synthesized ZCO NPs and ZCO PNCs was studied by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy techniques. The optical performance was characterized based on UV-visible-NIR data. The XRD investigations revealed the wurtzite structure of the ZCO NPs with a crystallite size of 17.8 nm. The FT-IR investigations confirmed the integration of ZCO NPs with the host blend’s structure. The optical analysis exposed that the direct and indirect band gap of the host blend decreased from 5.20 and 4.94 to 4.36 and 4.29 eV for 10 wt% of ZCO PNCs. The Urbach energy rose from 0.62 to 1.28 eV for 10 wt% of ZCO PNCs. The refractive index grew from 1.29 (bare blend) to 1.82 for 10 wt% of ZCO PNC at hν = 2.0 eV. In addition, a great enhancement in the non-linear optical constants was achieved via ZCO doping. The third-order non-linear susceptibility, χ (3), increased from 1.30 × 10−13 esu (bare) to 9.23 × 10−11 esu for 10 wt% of ZCO PNC at hν = 5.0 eV. We suggest these valuable achievements in the optical behavior of PVA/PVP/graphene blend by ZCO doping nominate it for applications in optical device improvement.