A droplet-based triboelectric-piezoelectric hybridized nanogenerator for scavenging mechanical energy

Water droplet energy has received much attention as a newborn renewable energy source. Triboelectric nanogenerators (TENGs) demonstrates enormous application in scavenging mechanical energy. Nowadays, the water droplet nanogenerator based on liquid-solid TENG has been greatly improved. However, these water droplet nanogenerators scavenge the mechanical energy of liquid-solid contact of water droplets by TENG, but not the deformation energy of the substrate. Here, we propose a new design strategy to increase the current of the water droplet nanogenerator through simultaneous scavenging of the mechanical energy of the liquid-solid contact and the deformation energy. A droplet-based triboelectric-piezoelectric hybridized nanogenerator (TPiHNG) with cantilever beam structure was fabricated under the strategy. The TPiHNG has a significantly higher current compared to TENG. The response time difference between piezoelectric nanogenerator (PiENG) and TENG is proposed for the first time as an important parameter of TPiHNG. This work provides a novel approach to scavenge water droplet energy more efficiently.