Metal ions-assisted construction of SiO2/MXene/Fe3O4 aerogel as multifunctional electromagnetic wave absorbing material

Advanced electromagnetic wave absorbing materials are developing towards the directions of lightweight, thin thickness, broad absorption bandwidth, and multifunction. MXene, as a new type of two-dimensional material, has received widespread attention, but it is necessary to address the impedance mismatch problem caused by its high conductivity. In this work, Fe3O4/MXene composite aerogel is prepared by metal ion-assisted crosslinking method without adding additional crosslinking agents. And a layer of hydrophobic fumed silica is further sprayed on the aerogel. Benefiting from the magneto-electric synergistic effect and the porous structure, SiO2/MXene/Fe3O4 aerogels shows excellent electromagnetic wave absorption performances, achieving a quite broad absorption bandwidth up to 8.8 GHz at an extremely thin thickness of 1 mm. The hybrid aerogel also shows superhydrophobic and thermal insulation properties, which are conducive to improving the resistance to harsh environments and thus endow the absorbers with a long service time. [Display omitted] •SiO2/Fe3O4/MXene aerogel is prepared by metal ion-assisted crosslinking method.•Magneto-electric synergy and porous structure improve impedance matching.•Aerogel shows a broad absorption bandwidth of 8.8 GHz at a thin thickness of 1 mm.•Aerogel shows superhydrophobic and thermal insulation properties.