Stretchable and Conductive Aerogel with High Thermal Insulation Through Surface Confinement of Liquid Metal Particles

The progression of wearable electronic devices has highlighted the need for flexible electronics that combine good conductivity with prolonged user comfort. However, simultaneously regulating the thermal and humidity comfort of the human body without compromising electronic performance remains a major challenge. This research introduces a liquid metal-embedded conductive aerogel (LeCA) to address the challenges of developing flexible circuits with high electrical performance, thermal insulation, and moisture permeability for wearable applications. By employing moisture absorption-induced phase separation in a thermoplastic polyurethane (TPU) matrix, an asymmetric porous structure is developed that decreases the thermal conductivity of the TPU film and spatially confines liquid metal particles to the upper layer of the TPU film. A direct writing method is demonstrated to facilitate the sintering of liquid metal particles into conductive patterns at targeted regions, resulting in an ease-of-fabrication manner for the development of flexible circuits. The findings present LeCA as a promising candidate for the development of wearable devices, combining the essential attributes of conductivity, thermal management, and user comfort in a single, flexible platform.