Exoskeleton-like mechanical enhanced low-density aerogel with electromagnetic interface shielding and infrared stealth

The integrated design and mechanical enhancement of multifunctional electromagnetic interference shielding and infrared stealth aerogels are challenging for the development and application of novel aerogels. Here, inspired by the biological exoskeleton to enhance the body, we develop the exoskeleton-like aramid nanofiber/polyimide/MXene (APM) aerogel through a secondary impregnation strategy. For APM aerogel, the polyimide reinforcement layer makes the aerogel more elastic and tough; the Ti3C2Tx-MXene exoskeleton enhances the strength and stiffness of the aerogel. Importantly, Ti3C2Tx-MXene forms a continuous conductive network on the surface of the airgel backbone, resulting in high-performance electromagnetic interference (EMI) shielding (EMI shielding efficiency reached 55.315 dB at an ultra-low Ti3C2Tx content of 0.58 vol%), high-efficiency infrared radiation (IR) stealth (ultra-low thermal conductivity of 0.0666 W·m−1·K−1 and IR emissivity of 0.566 at 3–5 μm and 0.55 at 8–14 μm). This study provides a way to design robust aerogel materials with infrared stealth and electromagnetic shielding compatibility.