Wake‐Induced Vibration Enhanced Triboelectric Nanogenerator for Efficient Energy Harvesting From Low‐Velocity Water Flows and Self‐Powered Sensing

ABSTRACT Low‐velocity water flows (<0.5 m s −1 ) remain largely underutilized due to the poor adaptability and high cut‐in thresholds of conventional generators. To address this limitation and fulfil the self‐powering demands of distributed sensors for river ecosystem monitoring, we report a wake ‐ induced vibration triboelectric nanogenerator (W ‐ TENG) that leverages flow‐induced instabilities for energy harvesting. By introducing an upstream bluff body, periodic vortex shedding is harnessed to amplify oscillation amplitude and contact frequency, thereby enhancing triboelectric charge generation. Systematic structural optimization and performance evaluation reveal the W‐TENG's remarkable adaptability to low‐speed aquatic environments, achieving an ultralow cut‐in velocity of 0.15 m s − 1 and a peak volumetric power density of 18.26 W m − 3 at 0.4 m s − 1 . To enhance energy conversion efficiency, an integrated energy management circuit is developed, enabling a 6.13‐fold increase in capacitor charging rate. As a proof‐of‐concept, the harvested energy is successfully used to power a wireless temperature sensor, enabling real‐time environmental data transmission to a mobile device without external power input. This work provides a practical and scalable approach for harvesting energy from water flows at low velocities and developing self‐powered sensing systems for river ecological monitoring.