Porous pure magnetic foam with engineered heterointerfaces for enhanced microwave absorption

Abstract

Despite significant progress in the structure and properties of porous absorbing materials, major challenges remain due to complex preparation technology, high production costs, and poor corrosion resistance. In this study, nanowires were used as the substrate, liquid nitrogen controls ice crystal growth orientation, and ammonia gas facilitates the generation of magnetic substances. The resulting pure magnetic porous foam (PMF) material exhibits enhanced performance in absorbing electromagnetic waves (EMWs) and improved corrosion resistance. The PMF's microstructure was analyzed for its dielectric and magnetic loss characteristics. The PMF combines a porous framework, nanoscale architecture, and exclusive magnetic components to create a lightweight foam absorbent material with enhanced magnetic dissipation capabilities. Among them, the Fe₄N PMF demonstrates an impressive minimum reflection loss (RL_min) value of −66.8 dB at a thickness of 1.09 mm, exhibits an effective absorption bandwidth of 4.00 GHz, and shows exceptional corrosion resistance with a self-corrosion potential of −0.65 V. Moreover, the effectiveness of the Fe₄N PMF in absorbing intelligent EMWs has been validated through radar cross-section (RCS) simulations. In summary, this study has developed electromagnetic wave-absorbing materials with slim profiles, lightweight properties, strong absorption capabilities, and excellent corrosion resistance. These characteristics make them highly promising for microwave absorption applications.