The bimetallic MXene/Fe3O4 composites with dielectric-magnetic synergy loss enable robust electromagnetic wave absorption

The proliferation of 5G technology has intensified electromagnetic wave (EMW) pollution, promoting the development of MXene absorbers for addressing the above issues. Ti3C2Tx MXene has attracted intensive attention due to its layered structure and superior conductivity. However, one MXene type and its single loss mechanism become frustrated under the increasingly complex electromagnetic environments. Herein, bimetallic solid-solution MXenes, decorated with Fe3O4 nanoparticles via electrostatic self-assembly, were synthesized. The solid solution of Nb/V induces the lattice distortion and alters atomic distribution, generating vacancy defects to serve as polarization centers. Theoretical calculation revealed that the form of electric dipole, resulting from charge density difference, significantly enhances polarization loss. The Fe3O4 incorporation optimizes impedance matching and introduces magnetic loss. Benefiting from synergy loss mechanisms, TiVCTx/Fe3O4 demonstrates the robust electromagnetic wave absorption (EMA) performance at a mass ratio of 1:1, achieving an effective absorption bandwidth (EAB) of 4.56 GHz at a thin thickness of 1.3 mm and the minimum reflection loss (RLmin) achieved at −43.59 dB. Notably, composites show an EAB of 1.36 GHz among low frequencies (3.92–5.28 GHz). This research provides a pathway for exploring bimetallic MXene, revealing its substantial potential for EMA applications in the context of the 5G era.