Highly efficient long-lasting triboelectric nanogenerator upon impact and its application to daily-life self-cleaning solar panel

Triboelectric nanogenerators (TENGs) have the potential to harvest energy from any type of movement; however, most TENGs are designed for low-frequency movement due to their low energy conversion efficiency with high-frequency movements such as impacts. In this paper, a TENG with high energy conversion efficiency and long-lasting output from impacts is proposed. This design is for a freely oscillating, non-contact TENG that employs a freely oscillating structure without frictional contact and which exhibits persistent output after impacts. It provides the capacity to light 20 LEDs for 10 s upon a single instantaneous impact. Owing to its freely oscillating structure, the energy conversion efficiency is up to 50.8%, which is significantly higher than that of other TENGs that use impacts. This platform was then applied to develop a self-cleaning solar panel system, which effectively removed 79.2% of the dust from the test panel surface after twelve impacts. Collectively, this work provides a strategy for harvesting energy from impacts and offers a useful application for self-cleaning solar panels.