About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
High-Entropy Materials: Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond VI
|
| Presentation Title |
Mn and Fe in Rock Salt Oxides: Thermodynamics-inspired High-Entropy Oxide synthesis |
| Author(s) |
Matthew Furst, Joseph Petruska, Dhiya Srikanth, Yueze Tan, Jacob T. Sivak, Gerald Bejger, Christina M. Rost, Susan B. Sinnott, Long-Qing Chen, Saeed S.I. Almishal, Jon-Paul Maria |
| On-Site Speaker (Planned) |
Matthew Furst |
| Abstract Scope |
Entropy-assisted synthesis stabilizes chemically disordered materials with properties distinct from their end members. The prototypical rock salt high-entropy oxide (HEO) MgCoNiCuZnO exemplifies this approach. Here, we construct phase diagrams that consider oxygen chemical potential to predict entropy-stabilized materials. Guided by these diagrams, we control oxygen level during synthesis and incorporate multivalent Mn and Fe into MgCoNiCuZnO – structures which are otherwise unstable in air. We synthesize seven equimolar single-phase rock salt compositions accommodating Mn and Fe using traditional firing techniques with binary oxide precursor powders. Results are confirmed by X-ray diffraction and fluorescence, and X-ray absorption fine structure spectra revealing predominantly divalent cations after reaction. Ultimately, we introduce oxygen chemical potential overlap as a key complementary descriptor for predicting HEO stability and synthesizability. Although we focus on rock salt HEOs, our methods provide a framework for navigating HEO thermodynamics and enabling a broader compositional range with contemporary property interests. |