MOF-derived multicore-shell Fe3O4@Fe@C composite: An ultrastrong electromagnetic wave absorber

Excessive artificial electromagnetic radiation poses significant health risks and disrupts military equipment. To address this, high-performance microwave absorption materials are urgently required. While ferromagnetic materials have excellent absorption but suffer from high density, limited bandwidth, and perishable properties. Carbon materials, especially metal-organic frameworks (MOFs), offer promise due to low density, chemical stability, and high conductivity. In this study, we synthesized a novel multicore-shell Fe3O4@Fe@C composite via solvothermal and in-situ pyrolysis methods. This composite integrated Zn-MOF-derived porous carbon with core-shell Fe3O4@Fe@C, enabling multiple electromagnetic wave routes, strong interfacial polarization, and magnetic-dielectric synergy. It exhibited exceptional electromagnetic wave absorption, with a -59.1 dB reflection loss at 13.36 GHz and a 5.36 GHz effective absorption bandwidth. Our innovative MOF-core-shell approach holds great promise for highly efficient microwave absorbers to mitigate artificial electromagnetic radiation's adverse effects on health and military equipment.