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 μA, 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.