High‐Current Triboelectric Nanogenerator Based on TiO ₂ ‐Decorated PVDF Membrane via Atomic Layer Deposition for Self‐Powered Humidity Sensing

Developing direct-current triboelectric nanogenerators (DC-TENGs) with high output performance and reliable operation in humid environments remains a significant challenge. In this study, we introduce a high-performance DC-TENG fabricated by integrating electrospinning, vapor-phase infiltration (VPI), and atomic layer deposition (ALD) to construct a TiO₂-modified polyvinylidene fluoride (PVDF) porous fiber (PTPF) membrane. The resulting PTPF10-TENG demonstrates superior electrical performance, generating a peak current of 0.72 mA, an output voltage of 1.79 V, and a maximum power density of 27.3 µW/cm², representing a 5.4-fold improvement over the porous PVDF membrane. Owing to its strong humidity-responsive behavior, the PTPF10-TENG also functions as a self-powered humidity sensor with a linear sensitivity of 0.0134 mA/%RH (R² = 0.981) in the 40-100% RH range. These findings underscore the versatility of the PTPF membrane as a multifunctional platform that bridges efficient energy conversion and environmental sensing. This strategy offers a promising route toward scalable fabrication of DC-TENGs tailored for next-generation wearable electronics and intelligent monitoring systems.