Room temperature electrochemical redox reactions of the defect perovskite SrFeO{sub 2.5 + x}

Journal Article · Tue Sep 01 04:00:00 EDT 1998 · Chemistry of Materials

DOI:https://doi.org/10.1021/cm980090v· OSTI ID:669760

Nemudry, A; Gainutdinov, I; Boldyrev, V ^[1]; Weiss, M; Schoellhorn, R ^[2]

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1. Russian Academy of Science, Novosibirsk (Russian Federation)
2. Technische Univ. Berlin (Germany). Inst. fuer Anorganische und Analytische Chemie

The electrochemical and chemical oxidation of the defect perovskite SrFeO{sub 2.5} to the cubic perovskite SrFeO{sub 3} at ambient temperature in alkaline electrolyte are shown to be in principle reversible processes with the appearance of intermediate compounds; the oxidation can be described by the formation of line phases SrFeO{sub 2.75} and SrFeO{sub 2.87} and one solid solution range SrFeO{sub 3{minus}x} with 0 {le} x {le} 0.03. The structure of the brownmillerite type parent phase is characterized by the presence of stacking faults in the octahedral and tetrahedral sequence of layers whose concentration increases significantly upon formation of the intermediate phases. Models based on observed microscopic features are discussed in order to explain the unusual phenomenon of room temperature oxygen transport.

• OSTI ID: 669760
• Journal Information: Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 9 Vol. 10; ISSN CMATEX; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHEMICAL REACTIONS
ELECTROCHEMISTRY
IRON OXIDES
OXIDATION
PEROVSKITE
REDUCTION
SOLID SOLUTIONS
STACKING FAULTS
STRONTIUM OXIDES