A reduction-driven directed aggregation strategy for fabricating stretchable conductive core-sheath fibers in wearable electronics

Rapid advancement of wearable electronics is profoundly reshaping our daily lives. At the heart of these innovations, stretchable conductive fibers (SCFs) assume pivotal roles in the high-sensitivity strain sensing and the high-conductivity flexible electrical conduction. Here, the stretchable conductive core-sheath fibers (SCCFs) are developed by a reduction-driven directed aggregation strategy. A conductive sheath layer of the silver nanoparticles aggregation and an elastic core layer of polymer matrix constitute an SCCF with the effective interface bonding. An SCCF with the high initial conductivity of over 1.77 x 105 S m-1 is fabricated with the features of reliability and good washability through the systematic optimization. On one hand, leveraging the microcrack effect, the strain sensing with the high resistance sensitivity under subtle strain is achieved by using a straight SCCF. On the other hand, the SCCF with a three-dimensional helical structure is designed to act as the flexible electrical conduction with the low resistance sensitivity under great strain. Notably, these SCCFs not only exhibit exceptional sensitivity for monitoring human movements, but also demonstrate efficient electrical energy conduction capabilities. This work proposes a prospective strategy to fabricate the versatile SCFs with great reliability, stability, and durability for wearable electronics.