A High-Output Triboelectric Sensor Enabled by Hierarchically Porous PVDF/BaTiO3 Composite Nanofibers for Self-Powered Biomedical Electronics

Abstract

Triboelectric nanogenerators (TENGs) based on poly(vinylidene fluoride) (PVDF) have attracted considerable attention for wearable and self-powered biomedical electronics due to their flexibility, biocompatibility, and favorable triboelectric properties. However, their relatively limited electrical output still hinders practical applications. Herein, a synergistic strategy integrating hierarchically porous structure engineering and barium titanate (BaTiO3, BTO) nanoparticle (NP) incorporation was developed to enhance the triboelectric performance of PVDF nanofiber membranes. In particular, the hierarchical porous structure increases surface roughness and effective contact area, thereby promoting interfacial charge generation. BTO NPs compensate for the reduction in effective dielectric permittivity associated with the porous structure. The synergistic effect of these two factors achieved a short-circuit current of 0.863 ± 0.027 μA, a transferred charge density of 25.99 ± 0.62 μC m−2, and a power density of 650 mW m−2. The output voltage increased to 64.44 ± 0.83 V, corresponding to a 204.8% enhancement compared with the pristine device. Finally, the device was attached to the elbow joint, the contact area of the arm, and the sole of a shoe to verify its ability to monitor human motion signals and power electronic devices. The results demonstrated that the sensors can effectively distinguish between different motion states and can power small electronic devices for harvesting mechanical energy. Overall, this study developed a simple yet highly efficient strategy for enhancing the electrical output capacity of PVDF-TENG and holds promising potential for practical applications in human physiological signal monitoring and self-powering wearable devices.