Thermodynamic properties for metal oxides from first-principles
Journal article, 2024

In this study, an efficient first-principles approach for calculating the thermodynamic properties of mixed metal oxides at high temperatures is demonstrated. More precisely, this procedure combines density functional theory and harmonic phonon calculations with tabulated thermochemical data to predict the heat capacity, formation energy, and entropy of important metal oxides. Alloy cluster expansions are, moreover, employed to represent phases that display chemical ordering as well as to calculate the configurational contribution to the specific heat capacity. The methodology can, therefore, be applied to compounds with vacancies and variable site occupancies. Results are, moreover, presented for a number of systems of high practical relevance: Fe–K–Ti–O, K–Mn–O, and Ca–Mn–O. For the reference materials, the agreement with experimental measurements is exceptional in the case of ilmenite (FeTiO3) and good for CaMnO3. When the generated data is used in multi-phase thermodynamic calculations to represent materials for which experimental data is not available, the predicted phase-diagrams for the K–Mn–O and K–Ti–O systems change dramatically. The demonstrated methodology is highly useful for obtaining approximate values on key thermodynamic properties in cases where experimental data is hard to obtain, inaccurate or missing.

Phase equilibria

Oxides

Specific heat

Ab initio calculations

Thermodynamic properties

Author

Joakim Brorsson

Chalmers, Physics, Chemical Physics

Ivana Stanicic

Chalmers, Space, Earth and Environment, Energy Technology

Jonatan Gastaldi

Chalmers, Space, Earth and Environment, Energy Technology

Tobias Mattisson

Chalmers, Space, Earth and Environment, Energy Technology

Anders Hellman

Chalmers, Physics, Chemical Physics

Computational Materials Science

0927-0256 (ISSN)

Vol. 233 112690

Mixed-up metals for chemical-looping combustion

Swedish Research Council (VR) (2020-03487), 2021-01-01 -- 2024-12-31.

Subject Categories

Energy Engineering

Metallurgy and Metallic Materials

Condensed Matter Physics

DOI

10.1016/j.commatsci.2023.112690

More information

Latest update

12/22/2023