Dual-mode thermal-regulating and self-powered pressure sensing hybrid smart fibers

Textiles are considered as the second skin of human beings, and one of its essential tasks is thermal management. Nowadays, textile-based wearable pressure sensing technology represents a fascinating developing trend due to its predominant breathability, moisture permeability, and excellent comfortability. At the same time, thermal-regulating textiles have also received extensive attention in academia and industrial fields, because they can provide personal thermal comfort for the human body. However, there are few textiles that have the dual functions of pressure sensing and thermal regulation. Herein, a novel and multifunctional smart fiber is fabricated by using a hollow silicone rubber fiber filled with a liquid metal (LM) electrode. It can automatically switch between heating mode and cooling mode to adjust microenvironment temperature around human skin through solid-liquid phase transformation of phase change materials (PCMs). In addition, as a self-powered pressure sensor, the fiber can respond to versatile mechanical stimuli, such as human walking, running, wrist movements, and joint bending at different angles. This work provides a feasible way for constructing multifunctional smart fibers, which show great application prospects in personal motion monitoring and real-time thermal regulation.