Morphology-dependent electromagnetic wave absorbing properties of iron-based absorbers: One-dimensional, two-dimensional, and three-dimensional classification

Owing to the fast development of wireless techniques at the high-frequency range, the electromagnetic interference problem has been of increasing significance and attracting global attention. It is urgent to develop efficient microwave absorbing materials to attenuate the harmful electromagnetic wave. Iron and Fe-based composites are advantageous in the low-cost and attractive magnetic properties, so they have been widely studied in microwave absorption. This review focuses on the latest advances in nanostructured Fe-based materials including nanostructured iron, Fe/C (carbon nanotubes, nanofibers, nanocapsules, etc.), Fe/semiconductor (TiO₂, MnO₂, ZnO, SiO₂, MoS₂, etc.), Fe/polymer (polyaniline and polypyrrole), FeCo alloy, etc. However, most of these Fe-based materials suffer from the poor impedance matching and oxidation, which seriously impede their implementation as high-performance microwave absorbing materials. In this review, the main synthesis and modification methods, as well as the practical performance of Fe-based microwave absorbing materials are discussed. Moreover, challenges and perspectives of Fe-based composites for further development in microwave absorbing materials are proposed.