Polymeric Nanocomposites Membranes with High Permittivity Based on PVA-ZnO Nanoparticles for Potential Applications in Flexible Electronics.

This study reports the optical, structural, electrical and dielectric properties of Poly (vinyl alcohol) thin films membranes with embedded ZnO nanoparticles (PVA/ZnO) obtained by the solution casting method at low temperature of deposition. Fourier Transform Infrared spectra showed the characteristics peaks, which correspond to O⁻H and Zn⁻O bonds present in the hybrid material. The X-ray diffraction patterns indicated the presence of ZnO structure into the films. The composite material showed low absorbance and a wide band of gap energy from 5.5 to 5.83 eV. The surface morphology for the thin films of PVA/ZnO was studied by Atomic Force Microscopy and Scanning Electron Microscopy. The electrical properties of the membranes were also characterized by current-voltage characteristics and the DC conductivity showed Arrhenius behavior with values of activation energy from 0.62 to 0.78 eV and maximum conductivity at 2.4 × 10-12 S/cm. The dielectric properties of the nanocomposites were measured from low to high frequencies, and the results showed a high dielectric constant (ε) in the order of 10⁴ at low frequency and values from ε ≈ 2000 to 100 in the range of 1 KHz⁻1 MHz respectively. The properties of PVA/ZnO such as the high permittivity and the low temperature of processing make it a suitable material for potential applications in the development of flexible electronic devices.