A nano-micro structure engendered abrasion resistant, superhydrophobic, wearable triboelectric yarn for self-powered sensing

Smart wearable electronics with harvest energy are rapidly developing in modern life. Fiber-based triboelectric generators (TENGs) are gaining extensive attention for energy harvesting and human motion sensing, due to flexible, lightweight, and comfortable properties. However, it is difficult to coordinate the high electrical output performance of fiber-based TENGs with the requirements of human wearing comfort (abrasion resistant, air permeability and skin-friendliness). Herein, a novel nano-micro structure yarn (NMSY) with three layers was proposed via combining conjugated electrospinning as well as ring spinning together. Therein, electrospinning Nylon 11 nanofibers were applied as the intermediate layer to enhance electrical output performance and ring spinning polyester fibers wrapped as the outermost layer to improve abrasion resistance. The obtained NMSY exhibits high output voltage (17.5 V in 3.5 cm) and wear resistance (4500 abrasion cycles). Furthermore, an electronic textile (e-textile) was knitted with NMSY (2.5 × 2.5 cm2), which exhibited a power density of 487.8 mW/m2 at a load resistance of 700 MΩ. Owing to the unique interconnected loop structure of knitted textiles, NMSY e-textile shows good air permeability (147.3 mm/s), water vapor transmission rate (3470 g/(m2·24h)) and excellent skin-friendly. In practical application, NMSY e-textile can lit up 22 LEDs and also can charge the commercial capacitors efficiently. Besides, NMSY as well as the corresponding e-textile can also be used as self-powered sensors to monitor body movement. In summary, the superior NMSY presented in this work could enhance energy harvest and wearability, which would pave the way toward full-fledged commercialization of the TENGs in the future.