About this Abstract |
Meeting |
2nd World Congress on High Entropy Alloys (HEA 2021)
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Symposium
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2nd World Congress on High Entropy Alloys (HEA 2021)
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Presentation Title |
Suppression of Disorder in High Entropy Oxides |
Author(s) |
Abhishek Sarkar, Benedikt Eggert, Ralf Witte, Johanna Lill, Leonardo Velasco, Qingsong Wang, Janhavika Sonar, Katharina Ollefs, Subramshu S. Bhattacharya, Frank M.F. de Groot, Richard A. Brand, Heiko Wende, Oliver Clemens, Horst Hahn, Robert Kruk |
On-Site Speaker (Planned) |
Abhishek Sarkar |
Abstract Scope |
Utilization of configurational entropy for designing novel functional oxides started with the discovery of high entropy oxides (HEOs). HEOs have already received enormous attention owing to the wide variety of compositions, crystallographic structures and distinctive properties. Hitherto reports have always considered random and non-preferential ionic arrangements in HEOs. However, recent case studies on high entropy alloys have shown that the deviation from complete disorder can substantially improve their properties. However, this aspect of fundamental importance remains unexplored in HEOs. This work provides a direct experimental evidence for extremely preferential cationic arrangement in a model spinel-HEO (S-HEO), in contrast to the previous reports that always assumed random occupation. To unambiguously unravel the cationic occupation in chemically-complex S-HEO a combined and cross-referenced spectroscopy, diffraction and magnetometery approach is followed here. The study highlights the importance of enthalpy parameters in HEOs as the occupation model indicates the state with the least configurational disorder. |
Proceedings Inclusion? |
Undecided |