Elaborately designed 3D honeycomb M−Ti3C2Tx@MoS2@C heterostructures as advanced microwave absorbers

Abstract

Microwave absorption materials with lightweight, high absorption performance, and a broad absorption bandwidth are becoming increasingly popular due to the rapid advancements in wearable devices and portable electronic products. The two-dimensional Ti3C2Tx MXene is a highly promising electromagnetic shielding material thanks to its excellent conductivity, rich functional groups and customizable surface chemistry. However, the low dielectric loss of this material restricts its applications in microwave absorption. Herein, 3D honeycomb M−Ti3C2Tx@MoS2@C heterostructures were synthesized by simple hydrothermal and secondary annealing methods. Vertically assembled MoS2 nanosheets ensured a large electromagnetic energy storage capacity and promoted additional interfacial polarization. The honeycomb surface structure facilitated the electromagnetic wave attenuation through multiple reflections. The carbon coating and M−Ti3C2Tx matrix resulted in high conductive loss in the final products. The three-dimensional honeycomb M−Ti3C2Tx@MoS2@C heterostructures demonstrated exceptional microwave absorption performance. When filler loadings reached 40 wt%, the 3D honeycomb M−Ti3C2Tx@MoS2@C heterostructures delivered a minimum reflection loss of −47.55 dB at a thickness of 4.0 mm, with the added benefit of increasing the effective absorption bandwidth to 4.02 GHz. These findings paved the way for the commercialization of advanced microwave absorbers.