Polar bear fur-inspired aerogel fiber with multi-mode thermal insulation and heating properties

The single passive insulation and the high infrared emissivity inherent in most textile materials prevent aerogel fibers from meeting the insulation requirements under extremely cold conditions. To address these issues, we mimicked polar bear fur, and prepared core-shell structured aerogel fibers using wet spinning-polymer coating technology. The porous structure of the core layer endows the aerogel with excellent insulation performance. The incorporation of MXene—chosen for its low mid-infrared emissivity and photothermal properties—into the coating dramatically reduced the aerogel fibers' emissivity to human body radiation from 0.94 to 0.64, enabling a 2.0 °C radiative heating effect. Additionally, under 1 sun illumination, the surface temperature of the aerogel fibers increases by 32 °C. By introducing functional materials into the coating through a simple method, we have achieved aerogel fibers that integrate passive porous insulation, radiative heating, and active photothermal effects, without affecting the basic structure of the aerogel fibers, thus expanding their application scope in harsh environments.