Broadband high-performance microwave absorption of the single-layer Ti₃C₂T_x MXene

MXenes, a family of two-dimensional (2D) materials, exhibit peculiar microwave-absorbing behaviors due to their unique chemical composition and structure. Although laminated Ti₃C₂T_x MXenes with a multi-layer structure have been used for microwave absorption, real 2D MXenes with a single-layer structure have not yet been investigated. Here, the electromagnetic wave response behavior of single-layer Ti₃C₂T_x MXenes was explored in detail. The permittivity of Ti₃C₂T_x MXene rises dramatically with an increase in filler loading, and Ti₃C₂T_x MXene features a distinct dielectric response wherein dipolar polarization and interfacial polarization makes a greater contribution at low filler loading; conductive loss becomes more prominent at high filler loading. Versus laminated Ti₃C₂T_x MXene, single-layer Ti₃C₂T_x MXene delivers superior absorbing capability: The RL_min value of SL-Ti₃C₂T_x-22% reaches −43.5 dB at 6.5 GHz, and a broad EAB of 6.88 GHz can be attained at a thickness of 1.8 mm due to enhanced dipolar polarization, interfacial polarization, and conductive loss. This work is of great significance in guiding the future development of MXene-based absorbers.