Wearable electronics need wires made from lightweight, flexible, strong, conductive, skin-friendly, and water-resistant materials. Silk has several of these properties, but is not conductive.
Yingying Zhang, Tsinghua University, Beijing, China, and colleagues have developed ultralight wires for wearable electronics in which conductive carbon nanotube (CNT) yarns are wrapped in flexible silk nanofiber films. The team prepared the CNT yarn by twisting a CNT sheet. An electrospinning process with a silk fibroin solution was then used to wrap this yarn in silk nanofibers. The CNT yarn was rotated during the process to provide a uniform silk nanofiber coating.
The wires have a good air permeability and a low weight, which makes them comfortable to wear. Their mechanical properties and their electrical conductivity are suitable for use in textile electronics. Post-treatment at 200°C under an argon atmosphere made the silk-coated wires splash-resistant by changing the structure of the silk proteins. According to the researchers, the developed fabrication method could also be useful for creating fibers from other materials.
- Splash-Resistant and Light-Weight Silk-Sheathed Wires for Textile Electronics,
Zhe Yin, Muqiang Jian, Chunya Wang, Kailun Xia, Zhehong Liu, Qi Wang, Mingchao Zhang, Huimin Wang, Xiaoping Liang, Xiao Liang, Youwen Long, Xiaohui Yu, Yingying Zhang,
Nano Lett. 2018.
https://doi.org/10.1021/acs.nanolett.8b03085