High-performance stretchable thermoelectric fibers for wearable electronics

Abstract

The development of miniaturized and wearable electronic devices addresses the demand for novel power-supply systems that have advantages including lightweight, good stretchability, self-sustaining and high compatibility with human skin. To meet these criteria, conducting polymer-based thermoelectric (TE) fibers have recently attracted extensive attention. However, the intrinsically stretchable TE fibers that simultaneously have good TE performance and stability under cyclic loading are still rarely reported. In this work, we have successfully produced high-performance stretchable TE fibers comprising of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) and waterborne polyurethane (WPU) via a simple one-step wet-spinning approach. In the composite fibers, WPU not only acts as an elastomeric matrix but also has a template effect on improving the packing order and increasing the linearity of the PEDOT chains during wet-spinning. As a result, the PEDOT:PSS/WPU composite fibers exhibited desirable wearable performance, including high power factor (26.1 μW m−1 K−2), good stretchability (>30%) and outstanding TE property stability under cyclic stretching. Their practical applications as stretchable temperature sensors and stretchable TE generators were further demonstrated. The high-performance and intrinsically stretchable TE fibers developed in this work are expected to be applied in various wearable electronics.