Orientation-dependent electrochemical reduction and proton evolution in the oxygen-deficient perovskite SrFeO2.5+y. (1st January 2023)

• Record Type: Journal Article
• Authors: Isoda, Yosuke; Kan, Daisuke; Majima, Takuya; Shimakawa, Yuichi
• Is Part Of: Applied physics express. Volume 16:Number 1(2023)
• Publication Date: 2023-01-01
• Subjects: transition metal oxides -- electrochemical control -- protonation -- epitaxial films; Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.35848/1882-0786/acac60
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: Electrochemical reactions with insertions of ions in solids depend on crystallographic orientations. We investigated electrochemical responses of (100), (110) and (111)-oriented oxygen-deficient perovskite SrFeO2.5+ y epitaxial films in electric-field-effect transistor structures with the proton-conducting electrolyte Nafion as a gate insulator. We found that only (100)-oriented SrFeO2.5+ y films exhibit changes associated with gate-voltage-induced electrochemical reductions. Furthermore, elastic recoil detection analysis shows that electrochemically reduced (100) films can accommodate protons, forming the proton-containing oxide H0.11 SrFeO2.5+ y . Our results show that oxygen vacancies form preferentially along the {100} axes and ion diffusion in electrochemical reactions occurs dominantly along the {100} directions in SrFeO2.5+ y .