About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
High-Entropy Materials: Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond VI
|
| Presentation Title |
Structural Systematics of a Fluorite-Type Solid Solution in Compositionally Complex Oxides |
| Author(s) |
Goretti C. Fraustro-Castaņeda, Sagrario M. Montemayor, William Reed, Eric C. O'Quinn, Maik K. Lang, Antonio F. Fuentes |
| On-Site Speaker (Planned) |
Antonio F. Fuentes |
| Abstract Scope |
Compositionally complex and high-entropy oxides represent a promising new class of materials with intriguing functional properties. Here, a complete series of compositions within a fluorite-type solid solution was synthesized via mechanochemical processing in a planetary ball mill, starting from elemental oxide mixtures: AO₂ (A = Ce, Zr, Hf) and Ln₂O₃ (Ln = Sm, Gd, Dy, Ho, Y). The tetravalent and lanthanide cations were kept at fixed atomic ratios, and the lanthanide content was systematically increased from 0 to 40 mol%. Phase evolution during milling was monitored, and the final products were characterized by synchrotron X-ray total scattering, confirming single-phase fluorite structures across the compositional range. Thermal stability was assessed by post-milling annealing. All compositions remained stable up to 1500°C, except those with 0 and 2 mol% lanthanide content, which decomposed at 1200°C. Structural and microstructural features were further analyzed, with X-ray pair distribution function (PDF) analysis revealing sub-nanoscale characteristics |