Flexible MXene/Cellulose\nNanofiber Aerogels for Efficient\nElectromagnetic Absorption

Abstract

Advanced electromagnetic (EM) wave absorbing materials\nwith maintained\nperformance after deformation are technologically important with the\never-developing flexible electronic devices. In this study, MXene/cellulose\nnanofiber (Ti₃C₂T<i>_x</i>/CNF) aerogels have been fabricated via selective etching and freeze-drying,\nand the effect of Ti₃C₂T<i>_x</i> content on the evolution of EM wave absorption properties\nhas been revealed. The addition of the Ti₃C₂T<i>_x</i> MXene nanosheets constructs an extensive\nnetwork for enhanced conductive loss and interfacial polarization,\ntogether with satisfactory impedance matching over a wide frequency\nrange. Optimal absorption can be achieved with 50.0 wt % MXene, exhibiting\na minimum reflection loss (RL_min) of −44.9 dB and\na broad effective absorption bandwidth (EAB) of 5.7 GHz at a thickness\nof 2.0 mm. After 50 cycles of bending deformation, the Ti₃C₂T<i>_x</i>/CNF aerogels exhibit\nmaintained performance due to the porous structure for stress dilution\nand the interlayer slipping benefiting from the existence of the Ti₃C₂T<i>_x</i> nanosheet. As\nsuch, this work provides not only an effective strategy to design\nflexible EM wave absorbers with excellent performance but also insights\ninto the evolution of absorption performance after multiple deformations.