Fiber-like Wearable Triboelectric Nanogenerator with Bionic Micro-Structure

Triboelectric nanogenerator (TENG) is capable of harvesting ubiquitous micromechanical energy by coupling triboelectrification and electrostatic induction with the small size, wide material selection, and simple production. Due to these advantages, the wearable TENG has become a popular topic to harvest the biomechanical energy generated by the human motions, which has well compatibility with skin. Here, a fiber-like wearable TENG (FW-TENG) based on single-electrode mode is fabricated by using polydimethylsiloxane (PDMS) as the cladding layer and fine spring as the conductive core. In a unique way of preparation, bamboo tube with the typical microstructure on the inner surface is used as the template of fiber in FW-TENG. The FW-TENG based on PDMS and fine spring with bionic microstructure presents extraordinary tensile properties, implying the outstanding ability of structural retention and fatigue resistance during wearing the TENG. Through systematically investigating and optimizing the operating conditions, the maximum open-circuit voltage (VOC) of 20 V and the short-circuit current (ISC) of 750 nA are obtained by FW-TENG with the length of 40 mm. Meanwhile, several FW-TENGs could be woven with spandex fiber that characterized by super-stretching, to amplify the output performance of FW-TENG. After converting the alternate signal into direct signal through a rectifier, the fiber-like wearable textile-based TENG (FWT-TENG) could light up ten LEDs simultaneously by palm tapping. It is worth mentioning that the electric signal is sensitive to the movement of the hand. In summary, this work provides a new method for fabricating FW-TENG applied to harvest biomechanical energy which have great application potential as wearable electronics in human-machine interaction systems.