Abstract:

Ti₃C₂T_x MXene's application as an efficient electromagnetic wave absorber (EWA) is hindered by its high reflection, low absorption, and poor mechanical strength. Inspired by structural engineering, we propose a heterogeneous assembly strategy to construct a novel 'reinforced concrete' structured Fe₃O₄/Ti₃C₂T_x MXene/CF@PANI (CPFT) composite. Through multi-scale structural design and interface regulation, the integration of mechanical enhancement and electromagnetic functionality has been achieved. The in-situ polymerized CF@PANI core-shell unit acts as both a reinforcing skeleton and a conductive bridge, enhancing mechanical stability and conductive loss. Simultaneously, mediated by polydopamine, Fe₃O₄ grows in-situ between the interlayers and on the surface of Ti₃C₂T_x MXene, forming a concrete-like matrix. The components self-assemble through electrostatic and hydrogen bonding interactions, resulting in a heterostructure with excellent interfacial compatibility. This significantly promotes interfacial charge accumulation and multiple polarization effects, optimizes impedance matching, extends the propagation and dissipation path of electromagnetic waves within the material, and achieves effective synergy between dielectric and magnetic losses. As a result, at 13.76 GHz, the CPFT-0.75 exhibits a minimum reflection loss of -37.34 dB and an effective absorption bandwidth of 3.28 GHz at a thickness of only 1.5 mm. Additionally, the CPFT-1.0 possesses good mechanical properties, with a measured Young's modulus of 20.8 MPa, tensile strength of 3.63 MPa, and elongation at break of 10.98%. This study presents a novel MXene-based functional material design through the integration of magnetic, conductive, and 2D nanomaterials within a hierarchical architecture that delivers a dual enhancement in both EWA and mechanical performance.

Key words: Ti₃C₂T_x MXene, Electromagnetic wave absorption, Surface-interface effect, Micro-structure design, Mechanical property