Optical and dielectric properties of PVC/TiO<inf>2</inf>/TBAI ionic liquid polymer electrolyte

Abstract

Polyvinyl chloride (PVC)/TiO2/x wt % tetrabutylammonium iodide (TBAI) polymers were formed using sol gel and casting methods. Rietveld refinement was used to investigate the structure and microstructure of TiO2. X-ray diffraction, Fourier transform infrared and energy dispersive X-ray analysis techniques were used to explore the present of TiO2 and TBAI over PVC matrix. SEM analysis was carried out to study the impact of loading the TiO2 nanofiller and TBAI on the surface morphology of host polymer. The possibility of using PVC/TiO2/TBAI in UV shielding is explored. The direct and indirect optical bandgap energies for PVC were reduced from (5.49, 5.15) to (5.47, 5) eV, respectively, as it was loaded with nano TiO2. Upon loading the PVC/TiO2 with different amounts of TBAI, the direct and indirect optical band gaps reduced further to (5.33, 4.61) eV and another two bands appeared (3.74–3.8, 2.96–3) eV for direct transition and (2.99–3.19, 2.19–3.36) eV for indirect transition. The values of dielectric constant, optical conductivity and nonlinear optical parameters became highest as the amount of TBAI became 25 wt % while the values of the surface and volume energy loss functions became highest as the content of TBAI became 5 wt %. The fluorescence intensity of the pristine PVC was greatly enhanced when it was loaded with TiO2. Further enhancement in luminescence intensity was obtained upon doping PVC/TiO2 with different weight percents (5, 10, 15, 20, and 25 wt%) from TBAI.