High-performance electromagnetic wave absorbers based on Fe-based MOFs-derived Fe/C composites

A combination of carbon materials and metal materials has received extensive attention of applications in electromagnetic wave (EMW) absorption. Herein, the porous Fe/C composites were fabricated by pyrolyzing FeMOFs precursor with different organic ligand ratios under Ar atmosphere. The Fe/C composites exhibited an excellent EMW absorption ability on account of the unique porous structure architecture, enhanced dipolar/ interfacial polarization between two components, improved multiple reflection and scattering, and better impedance matching. The EMW absorption performance of three kinds of porous Fe/C composites was studied in detail. Among them, the minimum reflection loss (RL) of FC-1 sample could reach 19.57 dB at a thickness of 2 mm with a better effective bandwidth (RL <= 10 dB) covering the whole Ku band. Notably, the optimal RL of FC-2 sample achieved 56.94 dB at a thickness of 3.1 mm, besides, the effective absorption bandwidth could reach 6.73 GHz with the thickness of only 2.5 mm. These results confirm that the as-prepared Fe/C composites with high-performance EMW absorption ability and broad effective bandwidth are a promising candidates as an EMW absorber.