Influence of mechanical motions on the output characteristics of triboelectric nanogenerators

Triboelectric nanogenerator (TENG) as an energy harvesting device, the output characteristics also affect its applications. Usually, the output characteristics of TENG are considered to be influenced by environmental factors, triboelectric materials, and surface morphology. Here we explore the output characteristics are also influenced by the mechanical motions of friction interfaces for the first time. And two new mechanical motions of TENG are proposed: coupling rotation contact-separation (CRCS) motion and independent rotation contact-separation (IRCS) motion. In addition, the output characteristics of TENG under different mechanical motions are investigated and revealed. It is a universal phenomenon that mechanical motions can affect the output characteristics of TENG verified by different types, different materials, and even different parameters of TENG. Compared with contact-separation (CS) motion, the transferred charges and output power of TENG under CRCS motion and IRCS motion realize 397%, 483% and 440%, 660% enhancement, respectively. Furthermore, the theoretical models describing dynamic charging and discharging under different mechanical motions are established. Finally, it is proved that changing mechanical motions can affect the collection of energy. This study provides a new factor to influence the output characteristics of TENG, which can guide the design and accelerate the practical applications of TENG.