Covalent assembly of carboxyl functionalized Ti3C2Tx with Amino-Fe3O4 for excellent electromagnetic wave absorbing property

The construction of a three-dimensional heterojunction interface and chemical modification can significantly enhance the electromagnetic wave absorption capability of composites. In this study, we successfully synthesized a covalently bonded carboxyl functionalized Ti3C2Tx (CFTC) complexed with Amino-Fe3O4 (CFTC-Fe3O4) through an amidation reaction followed by a post-annealing process, resulting in the homogeneous dispersion of NH2-Fe3O4 between CFTC layers. The innovative approach establishes a multi-layer heterojunction interface that effectively encapsulates magnetic nanoparticles with CFTC, thereby enhancing both interface polarization, defect polarization and conduction loss. The magnetoelectric synergy between CFTC and NH2-Fe3O4 improves impedance matching and endows the composites with exceptional electromagnetic wave absorption capabilities. Notably, the absorbers demonstrate an impressive minimum reflection loss of -50.95 dB at a thickness of 1.56 mm when the mass ratio of CFTC to NH2-Fe3O4 is 1:1 (designated as CTNF-2), accompanied by an effective absorption bandwidth of 4.76 GHz (12.32-17.08 GHz). This study presents a novel approach to developing highly efficient MXene-based absorbing materials through chemical modifications.