Why do oxygen-vacancies segregate to domain walls in BaTiO3?: Atomistic free-energy analysis

Azuma H, Ogata S, Kobayashi R, Uranagase M, Wendler F (2026)

Publication Type: Journal article

Publication year: 2026

Journal

Materials Letters Elsevier

Book Volume: 405

Article Number: 139755

DOI: 10.1016/j.matlet.2025.139755

Abstract

The segregation of oxygen vacancies (OVs) to ferroelectric domain walls (DWs) is believed to accelerate polarization fatigue. Previous theoretical studies relied on continuum methods and first-principles calculations at zero temperature. We conducted an atomically resolved free energy analysis of OV interactions with 90° and 180° DWs in tetragonal BaTiO3 using large-scale shell-model molecular dynamics with thermodynamic integration. The OV-formation free energy decreased by 30–50 meV owing to attractive OV-DW interactions, while the DW-formation free energy without OV ranged from 2 to 8 mJ/m2. These results indicate that the OVs segregate to DWs, and DWs can form spontaneously at a planar OV density of 1 nm−2.

Authors with CRIS profile

Frank Wendler Lehrstuhl für Werkstoffsimulation

Involved external institutions

Nagoya Institute of Technology / 名古屋工業大学 Nagoya Kōgyō Daigaku JP Japan (JP) RIKEN Center for Biosystems Dynamics Research JP Japan (JP)

How to cite

APA:

Azuma, H., Ogata, S., Kobayashi, R., Uranagase, M., & Wendler, F. (2026). Why do oxygen-vacancies segregate to domain walls in BaTiO3?: Atomistic free-energy analysis. Materials Letters, 405. https://doi.org/10.1016/j.matlet.2025.139755

MLA:

Azuma, Hikaru, et al. "Why do oxygen-vacancies segregate to domain walls in BaTiO3?: Atomistic free-energy analysis." Materials Letters 405 (2026).

BibTeX: Download