Improved electromagnetic wave absorbing in high-entropy few-layered MXene

Two-dimensional high-entropy (HE) MXenes are expected to be excellent electromagnetic wave absorbing (EWA) materials due to the good conductivity, surface functional groups, inherent defects/disorders, abundant dipoles, and large specific surface area. Here, we report the synthesis and EWA properties of HE few-layered (Ti1/5V1/5Nb1/5Cr1/5Mo1/5)4C3Tx MXene (HE-F-MXene), which demonstrated an optimal effective absorption bandwidth of 3.36 GHz (12.8–16.16 GHz, thickness of 1.3 mm) and a minimum reflection loss (RLmin) of −48 dB (12.48 GHz, thickness of 1.5 mm). The improved EWA performance is attributed to the synergistic effects of optimized impedance matching, balanced conduction loss, enhanced multiple polarization losses, and more adequate multiple reflections and scattering, collectively enabled by the HE effect, low-dimensional architecture, and the high-conductivity framework inherited from the HE-MAX precursor. This work will provide an efficient strategy for improving the EWA performance of MXenes through HE and low-dimensional engineering.