Factors Governing Oxygen Vacancy Formation in Oxide Perovskites

Area of Science:

• Materials Science
• Computational Chemistry
• Solid-State Physics

Background:

• Controlling oxygen vacancy (V_O) formation is crucial for metal-oxide-perovskite technologies.
• Accurate prediction of V_O formation energy is essential for materials design.

Purpose of the Study:

• To construct a compact linear model for neutral V_O formation energy in ABO₃ perovskites.
• To achieve reasonable fidelity with Hubbard-U-corrected density functional theory (DFT) calculations.

Main Methods:

• Developed a linear model using physically intuitive metrics like bond dissociation energies and reduction potentials.
• Validated the model against experimental data for solid oxide fuel cell materials.
• Utilized state-of-the-art exchange-correlation functionals in DFT calculations.

Main Results:

• Achieved a mean absolute error of 0.45 eV for perovskites stable at 298 K.
• Demonstrated accuracy across a diverse range of ABO₃ perovskites with various A-site (alkaline-earth metals, lanthanides) and B-site (3d transition metals) elements.
• Identified new candidate perovskites, such as (Bi,Y)(Fe,Co)O₃, with potential for thermochemical water-splitting.

Conclusions:

• The developed model offers accuracy, efficiency, and interpretability for V_O control.
• Facilitates high-throughput computational screening for materials discovery.
• Provides insights into the physics governing V_O formation in metal-oxide perovskites.