Fe-based multi-interfacial engineering composites for broadband electromagnetic wave absorption

This is the authors' abstract. We don't add key points for this paper.

Controlling phase composition and interfacial structures in electromagnetic waves (EMWs) absorbing composites is a promising approach to enhance absorption efficiency and integrate multifunctional properties. Here, we report the fabrication of iron-based nanostructured heterojunctions on reduced graphene oxide (rGO) via freeze-drying and controlled thermal treatment, enabling precise modulation of iron oxide phases. Among the obtained composites, the Fe₃O₄/Fe@rGO hybrid exhibited the strongest EMWs absorption. This enhancement originates from multiple loss mechanisms at the Fe₃O₄/Fe heterointerfaces, yielding a minimum reflection loss of −66.4 dB at 2.7 mm and an effective absorption bandwidth (EAB) of 7.16 GHz. Furthermore, a metal surface designed via full-wave simulations broadens the EAB to 15.3 GHz through optimized impedance and multi-resonance. The flexible Fe₃O₄/Fe@rGO film demonstrated high-performance infrared stealth, hydrophobicity, and efficient electromagnetic interference shielding. Density functional theory calculations revealed pronounced charge transfer at Fe₃O₄/Fe interfaces. Radar cross-section simulations further confirmed the material’s potential to substantially reduce detectability. This work presents a robust design strategy for next-generation electromagnetic protection materials with tunable composition, strong EMWs absorption, and integrated multifunctionality.