Impact of hybrid aluminum oxide/titanium dioxide nanoparticles on the structural, optical, and electrical properties of polyvinyl alcohol/ polyethylene glycol nanocomposites for flexible optoelectronic devices

This work investigates the impact of hybrid aluminum oxide and titanium dioxide nanoparticles (Al2O3/TiO2 NPs) on the properties of polyvinyl alcohol (PVA) and polyethylene glycol (PEG) nanocomposite films fabricated via solution casting. Transmission electron microscopy (TEM) analysis revealed an average crystallite size of 25-30 nm for the Al2O3 and TiO2, respectively. The X-ray diffraction (XRD) analysis revealed that the addition of hybrid Al2O3/TiO2 decreases the crystallinity degree of the PVA/PEG blend. Fourier Transform Infrared (FT-IR) analysis revealed that the main vibrational peaks of the PVA/PEG composite exhibited random variations upon filling with Al2O3/TiO2 nanoparticles. UV-Vis-NIR spectroscopy showed a decrease in transmittance and a new absorption peak at higher wavelengths with increasing nanoparticle concentration. The optical bandgap (Eg) calculated from the spectra also decreased. Dielectric properties, impedance, and AC conductivity measured at room temperature displayed significant enhancements with increasing nanoparticle content. Analysis of the impedance components (Z' and Z'') facilitated the determination of the equivalent electrical circuit for each sample. These findings demonstrate the potential of these nanocomposite films with improved electrical and optical properties for applications in optoelectronic devices.