Silk Fibroin-Carbon Nanotube Composites based Fiber Substrated Wearable Triboelectric Nanogenerator

The triboelectric nanogenerator (TENG) is an emerging technology that can convert mechanical energy generated by human motion into electricity, and it is expected to compensate batteries for driving wearable electronics. However, in the field of wearable TENGs, low cost and common wearable raw material, which is critical for daily use, cannot generate still higher output power as wearable TENG source. In this study, we developed a flexible fiber-substrated TENG (F-TENG) device based on silk and carbon nanotubes (CNTs) using electrospinning and electrospray. The F-TENG has a unique layered microstructure, which can provide a highly free wearing experience and usable output, while satisfying the requirements of being simple, durable, and flexible. The fabrication process subverts the conventional method of processing metal wires into fibers and weaving them into textiles at a later stage by converting a liquid solution to a thin film made of fibers. The two steps of electrospinning and electrospray can be conducted by using the same setup of equipment, under ambient conditions. The power generation capacity of the arch-shaped F-TENG reached 140.99 μW/cm2 with shaker patting and 317.4 μW/cm2 with hand patting. A series of wearing tests also showed high potential of its applications. Its tensile property was also proved to be able to meet the normal wearing requirements of daily life. The combination of silk and CNT, as well as the development of the processing methods, are able to lay a reliable foundation for the wearable TENGs to break through many current development bottlenecks.