An energy-coupled triboelectric nanogenerator based on charge pump for wind and water environments

As a promising technology, triboelectric nanogenerators (TENGs) can efficiently capture low-frequency energy to power distributed sensors. Wind and water are renewable energy sources that commonly co-exist in the environment, and their simultaneous harvesting has been a hot research topic for TENGs. However, existing researches are essentially the superposition of electrical energy converted from the single energy source, which lack the consideration of the unified conversion of the two energies. Here, we propose an energy-coupled triboelectric nanogenerator (EC-TENG) based on charge pump, which employs a savonius turbine and pelton wheel in conjunction with a system consisting of the main and pump unit to realize the coupling and unified conversion of wind and water energy. The effects on performance of EC-TENG are analyzed theoretically and experimentally. Compared with the sum of the outputs of the main and pump units, the peak power after coupling of the two units is significantly increased by 442.1%. EC-TENG can reach output performances of 7.5 mW and 412.2 mW/m2, and can stably supply power for the wireless temperature and humidity sensor at wind and water speeds of 3.5 m/s and 1.3 m/s, respectively. This work provides a reference for the research of TENGs with multi-energy collection.