High-performance self-poled PVDF-BaTiO 3 -CNT nanocomposites: A multifunctional material for flexible next-generation energy harvesting and sensing

This study presents a multifunctional nanocomposite based on poly(vinylidene fluoride) (PVDF) for applications in energy harvesting and sensing. We hereby report the synthesis of advanced nanocomposites that incorporate varying concentrations of barium titanate (BaTiO 3 ) nanoparticles and multi-walled carbon nanotubes (CNTs) through an optimized solution processing method. The fabricated composites achieve intrinsic piezoelectric properties without the requirement for external poling. The synergistic effects of BaTiO 3 (10–20 wt%) and CNT (0–1.5 wt%) concentrations were revealed using a concentration-resolved design matrix in which CNT loading was systematically varied within each BaTiO 3 level. The resulting composition-property relationships were comprehensively investigated through multi-scale characterization, including morphological, mechanical, and electrical analyses. The developed PVDF-based nanocomposite exhibits pronounced mechanical reinforcement, with Young’s modulus and tensile strength increased by 68% and 79%, respectively, relative to pure PVDF. The optimized nanocomposite delivers superior piezoelectric performance, achieving a d 33 of 66 pC/N and generating an open-circuit voltage of 25 V with a maximum output power of 345 μ W. Simultaneously, it exhibits an exceptional piezoresistive sensitivity of 20.6 kPa −1 , enabling dual-mode operation for high-performance energy harvesting and pressure sensing. By co-optimizing energy harvesting and sensing within a single multifunctional nanocomposite, this work provides a foundational platform for autonomous systems, enabling the development of next-generation smart skins and self-powered electronics.