A Novel Triboelectric Generator Based on the Combination of a Waterwheel-Like Electrode with a Spring Steel Plate For Efficient Harvesting of Low-Velocity Rotational Motion Energy

A waterwheel-like electrode combined with a spring steel plate is used to construct a novel triboelectric generator (WSTG) for efficient harvesting of low-velocity rotational motion energy. By utilizing a spring steel plate, the energy of a low-speed rotational motion is first transformed into elastic potential energy through elastic deformation stored in the device, and then the elastic potential energy is released into kinetic energy of high-speed motion. Thus, a high output current is obtained. With its unique five-blade, waterwheel-like structure, each of the electrodes can fully contact the polymer friction layer during the rotation process. The WSTG achieves a maximum current, voltage, and power density of 102 mu A, 612 V, and 3.12 W m(-2), respectively, in low-speed rotating motion. The working mechanism, robustness, and other factors that may affect the output performance are systematically studied. Moreover, a rotating speed and rotational angle sensor based on this WSTG is fabricated. The advantages of such WSTG working at low-speed rotational motion with high efficiency provide great potential applications in ambient energy harvesting.