A superhydrophobic droplet triboelectric nanogenerator inspired by water strider for self-powered smart greenhouse

With the widespread adoption of smart greenhouses, there is a significant increase in energy demand. Triboelectric nanogenerator (TENG) as an emerging energy harvesting technology has vast prospects for applications. Inspired by the water strider's ability to freely glide on the water surface, this study proposes a biomimetic superhydrophobic nanofiber film with rigid microstructures resembling the water strider's foot hairs as the negative friction layer material. It is utilized for constructing a superhydrophobic triboelectric nanogenerator (SH-TENG) for harvesting raindrop energy. The SH-TENG achieves an open-circuit voltage of 100 V and a shortcircuit current of 15 mu A. Furthermore, a theoretical model is proposed that relates the droplet release height to the droplet diffusion area. The correctness of this model is verified by experiments, providing further evidence for the process of converting droplet mechanical energy into electricity by SH-TENG. Finally, an SH-TENG with multiple top electrodes is proposed to continuously collect the energy of raindrops during falling. serving as a sustainable power source for self-powered environmental monitoring in smart greenhouses, corrosion protection of greenhouse steel frames, and electrically-stimulated pesticide controlled-release. This work provides a convenient approach for efficient collection of raindrop energy based on interface behavior control, which will guide the further development of droplet-based TENG towards higher performance and offer an innovative and sustainable solution to the energy supply issue in smart greenhouses.