Direct Assembly of Aerogel Micro‐Nanofiber/MXene Sponges with Dual‐Network Structures for All‐Day Personal Heating

Abstract Maintaining human body temperature under low temperature is crucial to human well‐being, thereby urgently requiring for high‐performance warmth retention materials. However, designing such materials with both mechanical robustness and warming up the human body under complex and changing outdoor environments remains challenging. Here, a dual‐network structured aerogel micro‐nanofiber/MXene sponge is directly synthesized by the synchronous occurrence of electrospinning and electrospraying. Tailoring phase inversion of the solution jet creates micro‐nanofibers with highly porous aerogel structures, which exhibit nanoscale aperture (30–60 nm) and high single fiber surface aera (56.5 m 2 g −1 ). Under strong hydrogen bonding interaction, the dual‐network structures are constructed by chemical entanglement between aerogel micro‐nanofibers and self‐assembled MXene networks, achieving robust stretchable and compressible property. The nanopores of the single fiber cause the Knudsen effect to suppress the slippage of air molecules, thereby enhancing the unique capacity to block heat energy. Further integrating passive radiative heating and active heating performance of MXene networks, the as‐designed sponge offers an all‐day personal heating system to rise human skin temperature over 3.5 °C. This work may provide new candidates for the applications within aerospace, energy, transportation, and building.