Ingenious microstructure design and a suitable multicomponent strategy are still challenging for advanced electromagnetic wave absorbing (EMA) materials with strong absorption and a broad effective absorption bandwidth (EAB) at thin sample thickness and low filling level. Herein, a three-dimensional (3D) dielectric Ti3C2Tx MXene/reduced graphene oxide (RGO) aerogel anchored with magnetic Ni nanochains was constructed via a directional-freezing method followed by the hydrazine vapor reduction process. The oriented cell structure and heterogeneous dielectric/magnetic interfaces benefit the superior absorption performance by forming perfect impedance matching, multiple polarizations, and electric/magnetic-coupling effects. Interestingly, the prepared ultralight Ni/MXene/RGO (NiMR-H) aerogel (6.45 mg cm-3) delivers the best EMA performance in reported MXene-based absorbing materials up to now, with a minimal reflection loss (RLmin) of -75.2 dB (99.999 996% wave absorption) and a broadest EAB of 7.3 GHz. Furthermore, the excellent structural robustness and mechanical properties, as well as the high hydrophobicity and heat insulation performance (close to air), guarantee the stable and durable EMA application of the NiMR-H aerogel to resist deformation, water or humid environments, and high-temperature attacks.
Keywords: Ti3C2Tx MXene; electrical/magnetic-coupling effects; microwave absorption; multifunction; oriented aerogel.