Liquid-Metal-Enabled, Bifunctional Core-Sheath Metafibers for Sensitive Biomotion Sensing and Radiative Personal Thermal Management

Combining radiative cooling with electronic sensing is crucial for the next generation of adaptive wearables. However, it remains challenging to achieve both efficient optical–thermal regulation and highly sensitive biomotion-sensing fiber architectures. Here, we develop porous core-sheath fibers that utilize the dual effects of liquid metal (LM) to integrate motion sensing and passive radiative cooling functions in a single fiber. The encapsulated LM microdroplets within the polymer act as both reconfigurable conductive networks and optical–thermal modulation units. These fibers exhibit excellent mechanical robustness, with an elongation at break exceeding 1000%. Owing to the piezoresistive LM network, the fibers exhibit sensing performance, featuring a strain detection limit of 0.01%, a response time of 62 ms, and a durability over 20000 cycles. Meanwhile, LM microdroplets serve dual roles as microscale reflectors and efficient heat transfer media. The synergistic effect between the porous polymer and LM microdroplets endows the fabrics with excellent radiative cooling capabilities, achieving a solar reflectance of 95.3% and a mid-infrared emissivity of 96.1%. Outdoor tests show the sustained subambient cooling of 5.2–6.3 °C and annual energy saving of 80–320 MJ/m 2 year −1 . Furthermore, these fibers enable simultaneous real-time gesture recognition and personal thermal management, thereby providing a versatile platform for multifunctional smart textiles.