Ru doped magnetic nanoparticles embedded in mesoporous silica for effective microwave absorption by interface engineering and DFT calculations

Strong absorption, thin thickness, wide-bandwidth as well as lightweight of microwave absorption materials (MAMs) are highly desirable. In this study, the mesoporous silica skeleton embedded by FeRu/(Fe, Ru)(3)O-4 magnetic nanoparticles (FR/FRO-mSiO(2)) were designed and fabricated by vacuum impregnation and reduction sintering methods. The minimum reflection loss (RLmin) of the FR/FRO-mSiO(2) composite with a metal mass ratio of 46% was-61.1 dB at a thickness of 2.0 mm, and the covered absorption bandwidth (RL < -10 dB) reached 6.8 GHz. In combination of Density functional theory (DFT) calculation, microstructure characterizations and electromagnetic characteristics, we found that the interface polarization and magnetic enhancement at the interfaces of FeRu-(Fe, Ru)(3)O-4, the local dipole moment, and the abundant propagation channels for the incident microwaves, endowed by the unique component and construction of FR/FRO-mSiO(2), contributed together to the excellent microwave absorption capability of FR/FRO-mSiO(2). This work provides a promising porous structure to broaden efficient bandwidth and strengthen microwave absorption intensity with lightweight.

Automated summary

A lightweight and porous microwave absorption material with strong absorption performance was designed and fabricated using vacuum impregnation and reduction sintering methods. The excellent microwave absorption capability of the material is attributed to factors such as interface polarization, magnetic enhancement, and abundant propagation channels.