First-principles analysis of the effect of magnetic states on the oxygen vacancy formation energy in doped La${}_{0.5}$Sr${}_{0.5}$CoO${}_3$ perovskite

Abstract

Oxygen vacancies are critical for determining the electrochemical performance of fast oxygen ion conductors. The perovskite La${}_{0.5}$Sr${}_{0.5}$CoO${}_3$, known for its excellent mixed ionic-electronic conduction, has attracted significant attention due to its favorable vacancy characteristics. In this study, we employ first-principles calculations to systematically investigate the impact of 3$d$ transition-metal doping on the oxygen vacancy formation energies in the perovskite. Two magnetic states, namely the ferromagnetic and paramagnetic states, are considered in our models to capture the influence of magnetic effects on oxygen vacancy energetics. Our results reveal that the oxygen vacancy formation energies are strongly dependent on both the dopant species and the magnetic state. Notably, the magnetic states alter the vacancy formation energy in a dopant-specific manner due to double exchange interactions, indicating that relying solely on the ferromagnetic ground state may result in misleading trends in doping behavior. These findings emphasise the importance of accounting for magnetic effects when investigating oxygen vacancy properties in perovskite oxides.

References in corpus (12)

• Structure and properties of functional oxide thin films: Insights from electronic-structure calculations
• TB2J: a python package for computing magnetic interaction parameters
• Orbital Ordering and Unfrustrated $(\pi ,0)$ Magnetism from Degenerate Double Exchange in the Iron Pnictides
• Effect of magnetic disorder and strong electron correlations on the thermodynamics of CrN
• Nano-magnetic droplets and implications to orbital ordering in La1-xSrxCoO3
• Strain-induced insulator state in La_0.7Sr_0.3CoO_3
• Interplay of octahedral rotations and breathing distortions in charge ordering perovskite oxides
• Effects of Strain on Orbital Ordering and Magnetism at the Perovskite Oxide Interfaces: LaMnO${}_3$/SrMnO${}_3$
• Theory of Half-Metallic Double Perovskites I: Double Exchange Mechanism
• Theory of Half-Metallic Double Perovskites II: Effective Spin Hamiltonian and Disorder Effects
• Role of oxygen vacancy in the spin-state change and magnetic ordering in SrCoO${}_{3-\delta }$
• Effects of paramagnetic fluctuations on the thermochemistry of MnO (100) surfaces in the oxygen evolution reaction