Boosting of structural, thermal, linear, and nonlinear optical properties of PVA/PVP blend using titanium dioxide filler

Abstract

AbstractIn the current work, a blend matrix that combines polyvinyl alcohol and polyvinyl pyrrolidone (PVA/PVP) was reinforced by titanium dioxide (TiO2) nanoparticles via the casting technique. The FTIR spectra and XRD examinations of nanocomposites offer insight into the structural changes that have taken place with the inclusion of TiO2 in the blend matrix. TiO2 elements were detected via the EDX detector linked to a scanning electron microscope (SEM). The transmission and absorption of the PVA/PVP‐TiO2 blend were evaluated via a UV–visible spectrophotometer. Tauc's model demarcated the optical bandgap (Eg), which declined from 4.91 eV for the pure to 4.66 eV for PVA/PVP—0.75 wt.%TiO2 film. The refractive index increases from 1.903 to 6.646 for pure blend and PVA/PVA/0.75 wt%TiO2, respectively. The nonlinear optical features (as predicted by the Wemple‐DiDomenico model) are enriched. The proliferation of TiO2 into the blend matrix significantly increased the third‐order nonlinear optical susceptibility χ(3), from 1.87 × 10−14 for pure blend to 5.091 × 10−13 for PVA/PVP‐0.75 wt.% TiO2, attributed to the oscillation of surface plasmons of TiO2 NPs. The thermal stability of the films was inspected. Doping the blend with TiO2 enhanced its thermal stability. The TiO2‐filled PVA/PVP films demonstrate hopeful features for various requests and can be utilized in optoelectronics and optical devices due to their tunable optical parameters and thermal stability.Highlights Thermal stability was enhanced with loading TiO2 nanoparticles in PVA/PVP matrix. The PVA/PVP–TiO2 films optical parameters were studied. Extinction coefficient and refractive index were enhanced with loading TiO2 in PVA/PVP matrix. Proliferation of TiO2 into the matrix significantly increased the nonlinear optical susceptibility of third‐order χ(3).