Composition-constrained rocksalt structure high entropy oxides with non-equimolar cations: Design and synthesis based on cluster-plus-glue-atom model

• Published in: Ceramics international Vol. 48; no. 17; pp. 25647 - 25650
• Main Authors: Yu, Yue, Liu, Shimin, Ren, Yuanwen, Xia, Zelin, Zhang, Shuang, Wang, Nan, Wang, Hualin, Jiang, Weiwei, Liu, Chaoqian, Ding, Wanyu, Zhang, Zhihua, Dong, Chuang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2022
• Subjects: Cluster-plus-glue-atom model; Composition design; High entropy oxides; Phase stability; Solid-state reaction; Phase stability; Solid-state reaction; Composition design; High entropy oxides; Cluster-plus-glue-atom model
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2022.05.265

High entropy oxides (HEOs) are an emerging material that is rapidly becoming a worldwide research hotspot due to its unique properties. The concept of HEOs was proposed based on the increased configuration entropy (Sconf). However, in a single-phase oxide with large Sconf, there is reversible transition from multi-phase to single-phase at low calcination temperature. Here, through a solid-state reaction experiment, XRD and EDS mapping characterization, a series of non-equimolar Mg–Co–Ni–Cu–Zn–O HEOs with single-phase rocksalt structure was designed and developed based on a cluster-plus-glue-atom model. It found that entropy-predominated phase transition temperature between a multi-phase and single-phase can be controlled by component optimization, and the thermodynamic stability of the system is improved.