Electrostatically self-assembled hierarchical magnetic Co7Fe3@C/Ti3C2Tx nanocomposite for high-efficient microwave absorption

Two-dimensional (2D) transition metal carbide (Ti3C2Tx MXene) possesses immense potential for electromagnetic wave (EMW) absorption. However, its absorbing performance is considerably restricted by spontaneous aggregation and a natural absence of magnetic loss. To address these challenges, a controllable electrostatic assembly strategy was introduced to construct hierarchical magnetic Co7Fe3@C/Ti3C2Tx nanocomposite. The hierarchical structure effectively isolated each electromagnetic element, ensuring effective synergy between the Co7Fe3@C particles and MXene nanosheets. Notably, the Co7Fe3@C/Ti3C2Tx nanocomposite exhibited a minimum reflection loss (RLmin) value of −64.9 dB at 1.9 mm and an effective absorption bandwidth (EAB) of 6.6 GHz at 2.5 mm. The remarkable microwave absorption (MA) performance could be ascribed to the synergistic effect of the 3D conductive network, a well-constructed micro-capacitor structure, and the highly dispersed hollow Co7Fe3@C, which improved impedance matching characteristics and enhanced EMW attenuation ability. The Radar cross section (RCS) simulation also confirmed the enormous practical application potential of the Co7Fe3@C/Ti3C2Tx nanocomposite. This study offers valuable insights for designing high-efficient MXene-based EMW absorbers with hierarchical structure.