CaTiO ₃ /ZnO‐PVDF Composite‐Based Triboelectric Nanogenerators for Self‐Powered Gait Sensing

Abstract In the context of the ongoing development of artificial intelligence and 5G technologies, a growing number of sensors are being integrated into the daily lives. Self‐powered wearable sensors based on triboelectric nanogenerator (TENG) represent an innovative solution to this trend, but the output performance of the flexible TENGs remains suboptimal. In this study, the band‐matched calcium titanate (CaTiO ₃ ) and zinc oxide (ZnO) nanostructures are prepared to form CaTiO ₃ /ZnO (CTO/ZnO) Schottky heterojunctions. The heterojunctions are subsequently doped into organic ferroelectric polyvinylidene fluoride (PVDF) to create flexible composite film, which significantly increases the dielectric constant through space charge polarization. Then the CTO/ZnO‐PVDF composite films served as triboelectric materials of the CaTiO ₃ /ZnO‐PVDF‐based TENG (CZP‐TENG). After optimizing the molar ratio of ZnO to CTO in heterojunction and weight ratio of CTO/ZnO in PVDF, both the output voltage and current density of the TENG are significantly improved, exhibiting a power density of 106.6 mW m ⁻² . Finally, the CZP‐TENG powers light–emitting diodes and a temperature sensor, serves as a wearable sensor, and enables self‐powered human body sensing, particularly in gait recognition for preventing of movement‐related diseases and injury rehabilitation.