Dielectric relaxation and optical modulation in PVC/TPU-BaSnO3/Sn2O3 nanocomposites for enhanced energy storage and optoelectronic performance

Abstract

This work involves the fabrication and comprehensive characterization of flexible polyvinyl chloride (PVC)/thermoplastic polyurethane (TPU)/BaSnO₃/Sn₂O₃ (BSO/SO) nanocomposites, with a focus on optimizing their structural, dielectric relaxation, and optical properties for energy storage and optoelectronic applications, and they were synthesized by co-precipitation and drop-casting procedures. The distinctive systems were examined using XRD, FTIR, HRTEM, and FESEM techniques, including the structural integrity of blends and nanocomposites. A BaSnO₃/Sn₂O₃ (BSO/SO) nanocomposite has been effectively integrated into the PVC/TPU blend, as demonstrated by microstructural characterization using XRD, EDX, and ATR-FTIR tools. Supplementation with nanoparticles elevated the crystallinity, improved interfacial contact, and optimized the filler distribution. The incorporation of BSO-SO nanofiller notably modifies the dielectric relaxation characteristics of PVC/TPU blends via mechanisms that include interfacial polarization, limited polymer mobility, and improved charge carrier dynamics, demonstrating a dielectric constant of 120, a twelvefold increase at higher concentrations of nanofiller at low frequencies. The amount of nanofiller in the PVC/TPU-BSO-SO composites greatly influences how they transmit and reflect light, improving their clarity, ability to block UV rays, and flexibility in terms of the optical properties. Pronounced reductions of the direct and indirect optical band gaps are seen. The changes in band gaps might be due to more disorder, changes in crystal structure, and the possible clumping of nanoparticles. The resulting nanocomposites combine flexibility with tunable dielectric and optical properties, positioning them as strong candidates for use in flexible energy storage, UV blocking, and optoelectronic applications.