High-entropy ceramics (HECs) are gaining significant interest due to their huge composition space, unique microstructure, and adjustable properties. Previously reported studies focus mainly on HECs with the multi-cationic structure, while HECs with more than one anion are rarely studied. Herein we reported a new class of HECs, namely high-entropy alumino-silicides (Mo_0.25Nb_0.25Ta_0.25V_0.25)(Al_0.5Si_0.5)₂ (HEAS-1) with multi-cationic and -anionic structure. The formation possibility of HEAS-1 was first theoretically analyzed from the aspects of thermodynamics and lattice size difference based on the first-principles calculations and then the HEAS-1 were successfully synthesized by the solid-state reaction at 1573 K. The as-synthesized HEAS-1 exhibited good single-crystal hexagonal structure of metal alumino-silicides and simultaneously possessed high compositional uniformity. This study not only enriches the categories of HECs but also will open up a new research field on HECs with multi-cationic and -anionic structure.

高熵陶瓷（HEC）由于其巨大的组成空间，独特的微观结构和可调节的性能而引起了人们的极大兴趣。先前报道的研究主要集中于具有多阳离子结构的HEC，而很少研究具有多个阴离子的HEC。在这里，我们报道了一种新型的HEC，即高熵铝硅化物（Mo _0.25 Nb _0.25 Ta _0.25 V _0.25）（Al _0.5 Si _0.5）₂（HEAS-1）具有多阳离子和-阴离子结构。首先根据第一性原理从热力学和晶格尺寸差异的角度对HEAS-1的形成可能性进行了理论分析，然后通过1573 K的固相反应成功合成了HEAS-1。 HEAS-1表现出良好的金属铝硅化物单晶六方结构，同时具有较高的组成均匀性。该研究不仅丰富了HECs的种类，而且将为具有多阳离子和阴离子结构的HECs开辟新的研究领域。