The core-shell structure of nitrogen-doped carbon coated Fe3O4 decorated MXene for broadband and efficient microwave absorption

In recent years, MXene has gained widespread attention in the field of microwave absorption (MA) due to its unique two-dimensional layered structure, excellent electrical conductivity, and chemically active surface. However, the MA mechanism of MXene is limited to dielectric loss alone, which poses a challenge in meeting the performance requirements of new absorbers. Therefore, to enhance the performance of MXene in MA, this paper successfully prepared Fe3O4/NC@MXene (FNCM) composites by modifying core-shell magnetic nanoparticles of nitrogen-doped carbon coated Fe3O4 (Fe3O4/NC) on MXene. By adjusting the dose of Fe3O4/PDA precursor, the impedance matching is further optimized. FNCM-2 demonstrates superior MA performance with a thickness of 2mm, achieving a minimum reflection loss (RLmin) of −54.41 dB and an effective absorption bandwidth (EAB) of 7.32 GHz. Meanwhile, the RLmin of the FNCM-1 sample at a thickness of 2 mm can reach −55.65 dB. The remarkable improvement in MA performance can be attributed to the synergistic effect of dielectric and magnetic losses, which optimizes impedance matching. This study is expected to provide insights for the development of efficient and broadband MXene-based MA materials.