MXene/PEO aerogels with two-hierarchically porous architecture for electromagnetic wave absorption

MXene aerogels have drawn much attention for electromagnetic wave (EMW) absorption application and the internal microstructure of aerogels has a prominent influence on EMW response behaviors. However, as far as we know, it is still a challenge to modulate the microstructure of MXene aerogels. Herein, MXene/PEO aerogels with two-hierarchically porous structure have been successfully constructed where the 3D porous network of MXene/PEO aerogels is assembled by MXene layers featuring with secondary pore structure, which hasn't been reported in other work. It has been demonstrated that the amount of added PEO is responsible for the microstructure of MXene/PEO aerogels, thus having a direct effect on their complex permittivity and impedance matching. The resultant MXene/PEO aerogels deliver excellent EMW absorption performance that a broad effective absorption bandwidth of 5.20 GHz and a minimum reflection loss value of −50.8 dB can be achieved. The attractive EMW absorption properties depend on the comprehensive contributions of multiple dissipation modes and better impedance matching. Overall, this work fabricated MXene aerogel with two-hierarchically porous structure to satisfy the strong absorption capability and lightweight requirements of future EMW absorbers.