Enhanced the structural, optical, electrical, and dielectric properties of PEO/CMC blend via TiO2 and ZnO nanoceramics: nanocomposites for capacitor applications

Flexible and high-performance dielectric materials are critical for modern energy storage systems. Herein, polymer nanocomposite (PNC) films, based on polyethylene oxide (PEO) and carboxymethyl cellulose (CMC) blend, were reinforced with TiO₂/ZnO nanoceramics. The nanoceramics were synthesized via a sol-gel route and incorporated into the PEO/CMC matrix at concentrations ranging from 0.2 to 1.6 wt.% through the solution casting method. Structural analysis confirmed successful nanofiller incorporation, reducing crystallinity from 86.9% to 65.7% and increasing amorphous content. FTIR and UV–Vis spectroscopy revealed interfacial interactions, decreasing optical band gaps and increasing Urbach energy, indicative of enhanced defect states. Dielectric performance of the PEO/CMC-TiO₂/ZnO PNC film with nanofillers’ content of 1.6 wt.% was markedly improved, with ε′ exceeding 10⁴ and tanδ reduced below 1.5 at low frequencies at an applied electric field of 50 kV.cm⁻¹. Where the capacitance–frequency analysis showed a notable increase in capacitance (0.1 μF to 8 μF), while electric modulus and Jonscher exponent analysis revealed a transition from dipolar to interfacial polarization and a conduction shift toward localized hopping. These enhancements position the TiO₂/ZnO-reinforced PEO/CMC system as a viable material for high-performance dielectric capacitors.

Graphical Abstract