Hybrid MoO₃/ZnO-doped PVOH/PVP polymer nanocomposites for advanced optoelectronic applications

Hybrid nanocomposite films of poly(vinyl alcohol)/poly(vinyl pyrrolidone) (PVOH/PVP) were successfully prepared via solution casting by incorporating 0.5 wt.% MoO₃ and varying ZnO concentrations (1.5–9 wt.%). X-ray diffraction revealed a reduction in crystallinity and an increase in the amorphous phase with higher filler content, favoring charge transport. FTIR confirmed strong hydrogen bonding and coordination interactions between the polymer matrix and MoO₃/ZnO nanoparticles. UV–visible analysis showed enhanced absorption and a red-shifted edge, with the direct optical band gap decreasing from 5.16 eV (pristine) to 3.27 eV (9 wt.% ZnO), while the Urbach energy increased, indicating structural disorder and localized states. AC conductivity and dielectric measurements demonstrated significant improvement with filler content, dominated by hopping conduction and Maxwell–Wagner–Sillars polarization, with Cole–Cole plots indicating non-Debye relaxation behavior. Thermal analysis revealed increased degradation temperatures and residual mass, indicating enhanced thermal stability due to strong polymer–filler interactions. Mechanical testing showed improved tensile strength and elongation at break, reflecting enhanced load-bearing capacity and flexibility. Overall, the nanocomposite containing 0.5 wt.% MoO₃ and 9 wt.% ZnO exhibited the best optical, electrical, and dielectric performance, making these materials promising for flexible optoelectronic and energy storage applications.