Influence of laser ablation preparation of MgO and Bi2O3 nanoparticles on the optical and dielectric behavior of the PVA/PEO polymer blend

Abstract

This study aims to optimize the optical and electrical performance of polyvinyl alcohol/polyethylene oxide (PVA/PEO) incorporated with magnesium oxide (MgO) and bismuth(III) oxide (Bi₂O₃) nanoparticles synthesized by pulsed laser ablation over different durations. XRD revealed that the MgO nanoparticles acted as nucleating centers, increasing crystallinity. The incorporation of Bi₂O₃ resulted in sharper peaks and improved phase ordering with a prolonged ablation time. The FTIR spectra showed strong interactions between the PVA/PEO blend and nanoparticles, mediated by hydrogen bonding and novel vibrational modes between the metal and oxygen. UV-DRS showed optical modification and redshift of the absorption edge with a prolonged ablation time, indicating improved nanoparticle homogeneity, size growth, and crystallinity. TGA demonstrated an enhancement in the thermal stability of the Bi₂O₃/MgO double-filler composite. Dielectric and AC conductivity studies demonstrated a frequency behavior consistent with Maxwell–Wagner–Sillars interface polarization. Increasing the ablation time resulted in a decrease in the dielectric constant and conductivity, which was attributed to the small size and good dispersion of the nanoparticles and the restricted charge mobility due to the interface adhesion force.