Constrained growth strategy of magnetic nanoparticles to enhance broadband microwave absorption of FeCo/C nanorod composites

The magnetic component is crucial for achieving a high absorption bandwidth within the microwave absorbing materials, while a high loading rate of magnetic particles often leads to agglomeration, which can degrade the absorption performance. The utilization of short-chain ligands generally enhances the constrained growth effect of carbon materials on magnetic particles in metal-organic framework (MOF) derived materials. In this study, a CoFe/C nanorod derived from a MOF composed of nitrilotriacetic acid and cobalt-iron metal ions has been successfully prepared. The MOF-derived method with constrained growth is employed to suppress the aggregation of alloy microparticles and maintaining a high magnetic particles. The optimized composite exhibits an effective absorption bandwidth (EAB) of 7.88 GHz that could cover the Ku-band. The excellent dispersion structure and high loading rates endowed by CoFe/C nanorods with constrained strategy, would contributed to the enhanced wideband microwave absorbing properties. These findings might provide new guidance for the fabrication of noval broadband microwave absorbing materials with high loading of magnetic nanoparticles.