High-Performance\nWearable Joule Heater Derived from\nSea–Island Microfiber Nonwoven Fabric

A three-dimensional (3D) hierarchical\nmicrofiber bundle-based\nscaffold\nintegrated with silver nanowires (AgNWs) and porous polyurethane (PU)\nwas designed for the Joule heater via a facile dip-coating method.\nThe interconnected micrometer-sized voids and unique hierarchical\nstructure benefit uniform AgNWs anchored and the formation of a high-efficiency\n3D conductive network. As expected, this composite exhibits a superior\nelectrical conductivity of 1586.4 S/m and the best electrothermal\nconversion performance of 118.6 °C at 2.0 V compared to reported\nwearable Joule heaters to date. Moreover, the durable microfiber bundle–PU\nnetwork provides strong mechanical properties, allowing for the stable\nand durable electrothermal performance of such a composite to resist\ntwisting, bending, abrasion, and washing. Application studies show\nthat this kind of Joule heater is suitable for a wide range of applications,\nsuch as seat heating, a heating jacket, personal thermal management,\netc.