Electrostatically self-assembled Fe3O4@SiO2/MXene 3D interlayered structure improves Ku-band microwave absorption efficiency of epoxy-based nanocomposites

It is challenging to develop lightweight and efficient frequency-selective microwave absorption materials due to the trade-off between impedance matching and microwave attenuation ability. This study proposes a multiple heterointerfaces engineering strategy via electrostatically assembling to construct Fe3O4@SiO2/MXene 3D interlayer structure, which fully exerted the synergistic effect of dielectric-magnetic components. The 3D interlayer heterostructure achieves good impedance matching due to electromagnetic coupling and extended microwave propagation path. Simultaneously, massive charge transfer and redistribution at multiple hetero-interfaces embedded in this structure boost the polarization relaxation and dielectric loss ability. Consequently, the prepared nanocomposites exhibit remarkable Ku-band microwave absorption efficiency (-60.9 dB at a thickness of 1.0 mm), and have demonstrated valid practicality via Tesla wireless transmission shielding experiments. This study opens exciting possibilities for progress in the structural design, facile preparation and practical application of high-performance Ku-band microwave absorption materials.