Modification of Structural, Optical, and Electrical Properties of PVA/PVP Blend Filled by Nanostructured Titanium Dioxide for Optoelectronic Applications

The PVA/PVP/TiO 2 films were prepared using different TiO 2 concentrations by solvent casting technique. An analysis was conducted to investigate the influence of TiO 2 on the characteristics of PVA/PVP blends. The FTIR, UV/visible spectroscopy, and electrical bridge circuits were used to characterize the prepared nanocomposite films. The structural changes of the nanocomposite relative to pure PVA/PVP are indicated by FTIR spectra. The optical studies demonstrate that by increasing the TiO 2 concentration inside PVA/PVP blends, the band gaps reduce from 5.40 eV for PVA/PVP to 4.20 eV for PVA/PVP/TiO 2 (10 wt%), also the refractive indices the nanocomposites increase from 1.2020 for PVA/PVP blend into 2.5380 for PVA/PVP/TiO 2 (10 wt%). Also, the transmittance decreased from 97.6% for PVA/PVP blend to approximately 55.4% at the largest concentration of TiO 2 . Additionally, studies were conducted on the parameters, as well, ac conductivity ( σ ac ). The outcomes of dielectric parameters of the prepared films are enhanced by the doping of TiO 2 with different concentrations and dielectric relaxation is observed. The hopping mechanism of PVA/PVP/TiO 2 films is supported by the ac conductivity. It is found that adding 10 wt% TiO 2 inside PVA/PVP matrix at 5 MHz increases the conductivity of the pure PVA/PVP blend by 4.46 times.