MXene/carbon fiber/polyimide composite aerogel for multifunctional microwave absorption

Lightweight, multifunctional microwave absorption materials with comprehensive performance have promising applications in practical and extreme application environments. In this paper, Ti3C2Tx MXene/short-cut carbon fiber (CF)/polyimide (PMCF) aerogels are prepared by freeze-drying and thermal imidization method, which have excellent mechanical properties, hydrophobicity, flame retardant, heat resistance, and microwave absorption performance. Thanks to the porous structure, the aerogel has a low density of 18.58 mg/cm3 and hydrophobic property. MXene and CF stabilizes the structure of the PMCF aerogels, and the compressive strength and compressive modulus of the aerogel are 683.33 kPa and 557.33 kPa, respectively. The synergistic effect of the structure and components gives the material dielectric loss capability for good microwave absorption. The minimum reflection loss (RLmin) of the aerogel reaches −61.96 dB, and the effective absorption bandwidth (EAB) is 3.97 GHz. Polyimide gives the aerogel heat resistance up to 500 °C and flame retardancy against alcohol burning. The excellent electromagnetic wave (EMW) absorption properties and comprehensive performance will make this material prominent in next-generation electronic devices and stealth equipment in real-world environments.