Urchin-like Fe3O4@C with core-shell structure modified 2D MXene for high-performance microwave absorption

Abstract

As a typical two-dimensional material, Ti3C2Tx MXene has been considered a novel potential microwave-absorbing material because of its outstanding metallic-like conductivity and rich surface functional groups. Unfortunately, the microwave absorption performance is constrained by its intrinsic high conductivity and single loss mechanism. Herein, an urchin-like Fe3O4@C hollow sphere with core-shell structure was built by hydrothermal and annealing processes, which was subsequently used to modify MXene via electrostatic self-assembly. The Fe3O4@C/Ti3C2Tx hybrid with 30 wt% Fe3O4@C loading displayed a minimum reflection loss (RLmin) value of –64.0 dB at a thickness of 3.32 mm and a maximum efficient absorption bandwidth (EABmax) of 3.02 GHz at 3.24 mm. The exceptional microwave absorption performance is mainly attributed to the impedance matching brought about by the special urchin-like core-shell structure of Fe3O4@C, as well as the rich interfacial polarization and multiple reflections/scatterings. This work offers a novel idea for the design of efficient MXene-based microwave-absorbing materials.