Graphene-Assisted Assembly of Electrically and Magnetically Conductive Ceramic Nanofibrous Aerogels Enable Multifunctionality

Ceramic aerogels are gaining increasing attention due to their low density, high-temperature resistance, and excellent chemical stability. However, conventional ceramic aerogels are hindered by their intrinsic brittleness and limited dielectric properties, which restrict their scalable manufacturing and multifunctional applications. Here, ultralight, biomimetic porous, electrically and magnetically conductive ceramic nanofibrous aerogels composed of silicon dioxide (SiO2) nanofibers, graphene, and metal-organic framework (MOF) derivatives are prepared through an ice-templating freeze-casting followed by annealing approach. The renewable SiO2 nanofibers form robust bonding points with graphene, constructing interconnected high-porosity aerogels with good mechanical resilience. This allows for efficient integration of MOF-derived magnetic nanoparticles associated with a synergistic mechanical enhancement. The synergies of the dielectric and magnetic components, combined with the uniformly arranged sheet-like cell walls which facilitate the outstanding electromagnetic wave absorption performance. Moreover, the hydrophobic ceramic aerogels showcase excellent magnetothermal conversion, contributing to the application in wireless therapy, antibacterial, and magnetothermal deicing. Furthermore, the nanofibrous aerogels exhibit good thermal stability and insulation properties, rendering them highly suitable for thermal management devices in extreme conditions. With the renewable, convenient, and scalable manufacturing method, these multifunctional ceramic nanofibrous aerogels thus hold great promise in electromagnetic protection, wireless heating, and next-generation thermal management devices.