Soft-bionic-fishtail structured triboelectric nanogenerator driven by flow-induced vibration for low-velocity water flow energy harvesting

To adapt to the low-velocity water flow closely related to human life, the natural energy can be efficiently harvested and used to power monitoring devices. Herein, a triboelectric soft fishtail (TE-SFT) driven by flow-induced vibration (FIV) effect is proposed based on the soft material synthesis technology. Specifically, inspired by the fishtail fin, a bluff body with the cross-section of fishtail-shaped is designed, and has a preferable vortex effect by fluid simulation. In power generation part, the triboelectric nanogenerator (TENG) is designed to act as an inertial pendulum structure by geometric method. Under the FIV effect, the TE-SFT driven by fishtail-shaped bluff body swings like a fish in the water and then brings the inertial pendulum to acquire the oscillation for harvesting energy from low-velocity water flow. The TE-SFT attains an open-circuit voltage (V-OC) of 200 V to 313 V at the flow velocities of 0.24 to 0.89 m/s. Additionally, after 30 days of water immersion, the V-OC of TE-SFT retains 96.81%. In demonstration, the TE-SFT is applied to power the temperature and humidity sensor through harvesting water flow energy. This work also provides a way for self-powered system based on the TENG and soft bionic fish in water environment.

Automated summary

This study proposes a triboelectric soft fishtail (TE-SFT) device driven by flow-induced vibration (FIV) effect, which can efficiently harvest energy from low-velocity water flow. Inspired by biomimicry design, the device can swing like a fish in water and generate energy from the oscillation. Experiment results demonstrate that the device can generate high voltage within a certain range of flow velocities, and it also exhibits good stability. This research provides a new approach for self-powered systems based on TENG and soft bionic fish.