Multi-heterointerface integration in nitrogen-doped Ti3C2Tx@Fe3O4 nanocomposites for superior microwave absorption

Engineering a lightweight and thin microwave absorber through the design of multiple heterogeneous interfaces represents a significant challenge. Here, we synthesized a nitrogen (N)-doped Ti 3 C 2 T x @Fe 3 O 4 (N–Ti 3 C 2 T x @Fe 3 O 4 ) nanocomposite with a sandwich-like structure through a solvothermal approach using hydrazine hydrate as the N donor. The numerous Ti 3 C 2 T x electron transfer pathways of Ti 3 C 2 T x enable the realization of a hierarchical conduction network within N–Ti 3 C 2 T x @Fe 3 O 4 . The introduction of defects through N doping and the integration of Fe 3 O 4 with Ti 3 C 2 T x are pivotal for enhancing the dipole polarization. The heterogeneous interfaces in N–Ti 3 C 2 T x @Fe 3 O 4 , coupled with Fe 3 O 4 components, substantially boost the electromagnetic wave (EMW) absorption performance of the composite. An optimal N integration and the loading of Fe 3 O 4 in Ti 3 C 2 T x result in an improved impedance matching of N–Ti 3 C 2 T x @Fe 3 O 4 . The synergistic effect of the improved impedance matching and the strong EMW attenuation capability endow N–Ti 3 C 2 T x @Fe 3 O 4 with enhanced microwave absorption (MA) properties. Specifically, at a thickness of 1.04 mm, the composite exhibits the effective absorption bandwidth (3.92 GHz; 14.08–18.00 GHz), surpassing that of Ti 3 C 2 T x . At a thickness of 0.98 mm, it exhibits a maximum reflection loss of −40.28 dB at 17.25 GHz, which substantially exceeds that of Ti 3 C 2 T x . Furthermore, it shows a maximum Radar Cross Section reduction of 21.32 dB cm 2 . A cotton fabric was coated with N–Ti 3 C 2 T x @Fe 3 O 4 , and it was found to exhibit enhanced heat conduction and dissipation, at rates 3.83 and 4.64 times greater than those of uncoated cotton, respectively. These results highlight the considerable potential of N–Ti 3 C 2 T x @Fe 3 O 4 nanocomposites for use in far-field applications. It is envisaged that the exceptional MA and thermal management properties of N–Ti 3 C 2 T x @Fe 3 O 4 nanocomposites will provide a novel avenue for crafting lightweight and thin EMW absorbing materials.