Bidirectional, ultrathin Fe-MXene/GO aerogel with enhanced microwave absorption, thermal conduction, and mechanical stability

MXene-based materials with integrated electromagnetic wave (EMW) management and thermal dissipation capabilities exhibit considerable application potential for ensuring the stable service of electronic devices. However, existing regulation strategies struggle to realize the synergistic optimization of impedance matching and thermal conductivity simultaneously, which hampers its practical applications. Herein, by combining component modification and structural regulation strategies, a highly interconnected, anisotropically ordered Fe-MXene/graphene oxide (GO) aerogel was constructed via a modified bidirectional freeze-induced self-assembly technique. At the microscale, the electron-phonon thermal conduction mode of MXene-based materials is further enhanced by the long-range ordered lamellar structure and interlamellar bridging effect, endowing Fe-MXene/GO-1 with a thermal conductivity of 0.69 W m −1 K −1 —an increase of several tens of times compared with conventional aerogels. Meanwhile, the multiple reflections of EMWs by the porous architecture and the modulation of electrical conductivity via the electronic pinning effect synergistically optimize the EMW dissipation capability, granting Fe-MXene/GO-1 an effective absorption bandwidth (EAB) of 4.08 GHz along the axial direction at an ultrathin thickness of 1.45 mm. The results demonstrate that the introduction of a highly anisotropically ordered structure enables the synergistic enhancement of thermal dissipation capability and electromagnetic compatibility for the Fe-MXene/GO aerogel. Furthermore, the hydrogen-bonding interactions between intrinsically high-strength GO and Fe-MXene nanosheets effectively protect the aerogel skeleton and thus enhance its mechanical stability. This lightweight and thin Fe-MXene/GO aerogel exhibits tremendous potential for the packaging of highly integrated electronic devices.