Construction of Fe3O4@Ti3C2Tx Heterostructure for High-Performance Microwave Absorption via Synergistic Dielectric-Magnetic Loss

The escalating challenge of electromagnetic pollution demands the development of high-performance microwave absorption materials. Herein, a novel Fe3O4@Ti3C2Tx heterostructure is strategically constructed via in-situ chemical co-precipitation to address this issue. Two-dimensional Ti3C2Tx MXene, synthesized by etching Ti3AlC2 with a LiF/HCl mixture, serves as a conductive scaffold with an expanded interlayer spacing and an accordion-like morphology. Magnetic Fe3O4 nanoparticles are uniformly anchored within the interlayers and on the surface of Ti3C2Tx, forming abundant magnetic-dielectric interfaces. The successful intercalation and formation of Fe3O4 are confirmed by X-ray diffraction and X-ray photoelectron spectroscopy. By tailoring the Fe3O4-to-Ti3C2Tx mass ratio, the optimized composite (1:1) achieves an exceptional minimum reflection loss of -50.2 dB at a thin thickness of 2.0 mm, with an effective absorption bandwidth covering 5.1 GHz. This superior performance is attributed to the synergistic effects of the conductive network from MXene, magnetic loss from Fe3O4, optimal impedance matching, and intensified interfacial polarization.