Lattice distortion boosted exceptional electromagnetic wave absorption in high-entropy diborides

Abstract

Electromagnetic pollution has emerged as a severe global issue due to the widespread use of wireless communication, which strongly requires high-performance electromagnetic wave absorbents. Here, we realize exceptional electromagnetic wave absorption performance with an effective absorption bandwidth of 7.2 GHz at an ultralow thickness of 1.5 mm in high-entropy diborides through a lattice distortion engineering strategy. Particularly, we rationally tailor the lattice distortion of high-entropy diborides by manipulating constituent metal elements, and the resultant metal vacancies and chemical nanoclusters are verified to result in enriched electromagnetic wave absorption mechanisms, including (1) metal vacancy-induced dipole polarization loss, (2) metal vacancy-induced conduction loss, and (3) chemical nanocluster-induced interfacial polarization loss. Our work provides a simple and universal approach for effectively enhancing the electromagnetic wave absorption performance of ceramic absorbents.