Lightweight, self‐cleaning and refractory FeCo@MoS 2 PVA aerogels: from electromagnetic wave‐assisted synthesis to flexible electromagnetic wave absorption

Abstract The emergence of wearable and foldable electronic devices urges advanced electromagnetic (EM) wave absorbers with maintained performance under deformation. Here FeCo@MoS 2 poly vinyl alcohol (PVA) aerogels have been fabricated with the assistance of EM waves for simultaneous splitting of the MoS 2 flakes and dispersive growth of FeCo nanoparticles. The resultants in‐return have been used for EM wave absorption with excellent performance, providing minimum reflection loss (RL min ) of −40.7 dB and a broad effective absorption bandwidth (EAB) of 6.4 GHz at a thickness of 2.5 mm. Real‐time compression has been introduced to reveal the evolution of EM parameters. The aerogels maintain satisfactory performance even under 50% compression due to the balance of impedance matching and attenuation. Despite the deterioration of impedance matching, the attenuation is significantly enhanced due to both strengthened conductive loss and magnetic loss. In addition, features such as lightweight, self‐cleaning and refractory can be achieved for the aerogels for applications in complex environments. As such this work not only provides a versatile synthetic route assisted by EM wave energy, but also insights on the evolution of absorption performance under deformation together with the design strategy of multifunctional flexible wave absorbers.