Heterostructured MXene/Ni Composites for Tunable Electromagnetic Wave Absorption

Designing an absorber to mitigate the electromagnetic radiation pollution caused by the rapid development of radio technology with multiple characteristics, including high reflection loss (RL), broad absorption bandwidth, thinness, and low filling ratio, is crucial but challenging. This work prepared three-dimensional heterogeneous MXene/Ni composites by using an electrostatic self-assembly method. Due to the synergistic effect of dielectric loss, magnetic loss, and the unique heterogeneous structure, the obtained multilayer MXene/Ni composites, with a low filling ratio of 15 wt % and a thickness of only 1.5 mm, achieved an astonishing minimum RL value of −79.6 dB and an effective absorption bandwidth (EAB) of 3.35 GHz. Furthermore, an ultrawide tunable EAB of 12.35 GHz could be obtained in the frequency range of 3.30–15.65 GHz by adjusting the matching thickness of the samples. This design of a heterogeneous interface structure provides a practical strategy to develop high-performance next-generation electromagnetic absorbers.