Engineering Janus Nanofiber Interfaces for Simultaneous Triboelectric Enhancement and Wearable Comfort

ABSTRACT Wearable triboelectric nanogenerators (TENGs) enable self‐powered health monitoring by sensing human motion and physiological signals. However, operating at the skin/device interface is usually compromised by perspiration. Here, we present a moisture‐wicking Janus bilayer TENG (MW‐JBT) that integrates directional moisture transport with dielectric‐engineered electrospun nanofibers. The Janus bilayer membrane integrates a tribo‐negative hydrophobic poly(vinylidene fluoride‐co‐hexafluoropropylene)/barium zirconate titanate‐silver core–shell nanoparticle (PVDF‐HFP/BZT‐Ag) nanocomposite layer with a hydrophilic polyurethane (PU) layer. In this architecture, the PVDF‐HFP/BZT‐Ag side functions as the charge‐generating interface, where BZT‐Ag core–shell nanoparticles promote dielectric polarization and retention, while the PU side facilitates moisture removal from the interface. Unlike conventional water‐resistant TENGs blocking moisture penetration, the asymmetric PVDF‐HFP/PU architecture establishes a capillary‐driven moisture pathway that actively removes interfacial sweat from the triboelectric surface within 4s. The optimized MW‐JBT achieves peak‐to‐peak outputs of 5.26 µA and 372 V at 100 N and 4 Hz, with a maximum power density of 17 W m − 2 . Integrated into a plantar sensing system with a wireless STM32 module and a Minimal RNN classifier, the MW‐JBT achieves 88.5% accuracy for fall detection. This work provides an interface‐engineered strategy to construct wireless sensors combing self‐powered sensing and wearable comfort, enabling home‐based healthcare and rehabilitation monitoring scenarios.