Abstract Scope |
Following the concept of metallic high entropy alloys, a first publication on a single phase oxide with 5 transition metal cations triggered an enormous increase of research efforts in the field of high entropy oxides (HEO). Meanwhile, many different systems with rocksalt, fluorite, perovskite, spinel, etc., structures have been prepared by a multitude of chemical, mechanical and physical synthesis techniques, in the form of powders, bulk structures and thin films. In addition to the different crystallographic structures and elements incorporated in HEO, the complexity becomes enormous if non-equiatomic compositions are considered. The enormous number of possible compositions has initiated recently efforts in high throughput synthesis and characterization. Electrochemical, catalytic, magnetic, and optical properties, some with potential for applications, have been studied for the different systems. An overview of the current status of the research on compositionally complex oxide powders and ceramics is presented. |