Superelastic and Electronic Conductive MXene Aerogels Enable Absorption-Oriented Electromagnetic Interference Shielding.

Electronically conductive MXene aerogels with superelasticity hold immense potential in flexible electromagnetic interference (EMI) shielding due to the responsive deformation under external stress. However, fabrication of superelastic MXene aerogels, which can automatically restore the initial shape without degraded shielding performance after a compression cycle, still confronts the cutting-edge challenge owing to weak van der Waals interactions. Herein, superelastic and electronically conductive MXene/guar gum/cellulose nanofibers (MGC) aerogels with extremely reversible compressibility and satisfactory shielding effectiveness are fabricated with the aid of unidirectional freeze-drying. Fortunately, dual hydrogen bonding interactions facilitate the formation of superelastic skeletons and prevent interlayer peeling during mechanical deformation; guar gum/cellulose slow down the sharp stress change through harvesting mechanical energy, unidirectional macropores, and functional groups significantly induce absorption-oriented EMI shielding performance. In view of the comprehensive performance, MGC-50 aerogels display a maximum EMI shielding effectiveness of 40.21 dB with high absorption efficiency (A coefficient = 0.9998), and importantly, the aerogels retain over 93.4% of the initial shielding effectiveness and maintain a shape recovery rate of 92.1% even after 100 compression/release cycles. The innovative design of dual hydrogen-bonding-assisted compressible MXene aerogels may inspire a theoretical foundation and preliminary guidance for the generation of wearable aerogels in EMI protection.