About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
|
Symposium
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Ceramics for New Generation Nuclear Energy System Application
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Presentation Title |
Oxygen Vacancy Formation Energetics in MgO-based High Entropy Oxides from DFT and Experimental Validation |
Author(s) |
Oriyomi Opetebu, Ting Shen, Rajendra Kumar Bordia, Dilpuneet S. Aidhy |
On-Site Speaker (Planned) |
Dilpuneet S. Aidhy |
Abstract Scope |
In contrast to single or double cation based oxides, high entropy oxides (HEOs) consist of equi- or near equimolar concentation of multiple cations randomly distributed on a crystal lattice. The random distribution causes a wide diversity of nearest-neigbor environments around oxygen atoms. Consequently, a range of bonding environments and oxygen vacancy formation energies are observed. We investigate oxygen vacancy formation energies in Mg(ZnCoNiCu)O-based HEO using density functional theory. Experimentally, a series of binary and HEO were synthesized using a simple and scalable polymeric steric entrapment method. By annealing in inert environment, oxygen vacancies were created in some of the and verified by XPS, TGA. We elucidate the variations in oxygen vacancy formation energies due to different cations and correlate to experimental observations. This understanding contributes to oxygen vacancy transport useful in microstructure evolution and electrochemical applications. |