Exceptional Electromagnetic Wave Absorption in High‐Entropy Carbides Enabled by Lattice Distortion Engineering

ABSTRACT The growing concern over human health issues, driven by increasingly severe electromagnetic pollution from 5G communication, has made the urgent development of high‐performance electromagnetic wave (EMW) absorbing materials. Although carbide‐based materials are promising because of their conductive and polarization losses, existing single‐component materials fall short of future requirements. We report a lattice distortion engineering strategy to design and synthesize a stable high‐entropy carbide (Ta 0.2 Nb 0.2 Ti 0.2 Zr 0.2 Cr 0.2 )C. The lowest reflection loss reaches −62.40 dB, and it exhibits an effective absorption bandwidth (EAB) of 6.39 GHz, a fourfold enhancement compared to that of the single component material TaC. Results indicate that severe lattice distortion in the high‐entropy composition induces the formation of high‐density defects, and the presence of metal vacancies significantly enhances the high‐entropy carbides conduction loss and dipole polarization. Concurrently, the abundant grain boundaries and hyper‐dense distorted lattices provide significant interfacial polarization and relaxation polarization, effectively broadening the electromagnetic absorption bandwidth. Electron holography analysis confirmed that a substantial accumulation of positive and negative charges at nano‐interfaces leads to an anomalous dielectric polarization loss. This study contributes an effective pathway for designing potent single‐phase electromagnetic wave absorption materials and provides a paradigm for improving other properties of high‐entropy carbides via the lattice distortion strategy.