Abstract: Multifunctional compatible stealth materials have emerged as the focal point of contemporary protection technology research and vanadium-based nanomaterials play a pivotal role in the development of advanced stealth materials. Here, a compatible stealth aerogel is successfully synthesized by employing mixed-valence decavanadate as the vanadium oxide (VO_x) molecular model. Ultralight {V^ⅣV^V₉}/MXene aerogel (0.0429 g cm^-3) exhibits exceptional radar stealth performance with a minimal reflection loss (RL_min) of -57.74 dB (99.9998 % EMW absorption) and a significantly superior radar cross section reduction value of 26.77 dB m². The aerogel's exceptional properties, including a low infrared (IR) emissivity (0.479) and a low thermal conductivity of (32.30 mW m^-1 K^-1), are crucial for enabling compatibility with IR and thermal stealth technologies. The presence of a mixed-valence polyoxovanadate cluster leads to an increase in the Schottky barrier and enhances magnetic properties, consequently boosting interfacial polarization and contributing to magnetic losses during electromagnetic wave (EMW) absorption. Consequently, altering the number of valence electrons significantly enhances the compatible stealth capabilities. These findings contribute significantly to our comprehension of how microstructure impacts EMW absorption processes and provide a basis for further research into the development of VO_x-based compatible stealth materials.

Key words: Polyoxovanadates, Electromagnetic wave absorption, Compatible stealth, Decavanadate aerogels, Schottky junction