Structural evolution of epitaxial SrCoO{sub x} films near topotactic phase transition

Journal Article · Tue Dec 15 00:00:00 EST 2015 · AIP Advances

DOI:https://doi.org/10.1063/1.4938547· OSTI ID:22492224

Jeen, Hyoungjeen ^[1]

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1. Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

Control of oxygen stoichiometry in complex oxides via topotactic phase transition is an interesting avenue to not only modifying the physical properties, but utilizing in many energy technologies, such as energy storage and catalysts. However, detailed structural evolution in the close proximity of the topotactic phase transition in multivalent oxides has not been much studied. In this work, we used strontium cobaltites (SrCoO{sub x}) epitaxially grown by pulsed laser epitaxy (PLE) as a model system to study the oxidation-driven evolution of the structure, electronic, and magnetic properties. We grew coherently strained SrCoO{sub 2.5} thin films and performed post-annealing at various temperatures for topotactic conversion into the perovskite phase (SrCoO{sub 3-δ}). We clearly observed significant changes in electronic transport, magnetism, and microstructure near the critical temperature for the topotactic transformation from the brownmillerite to the perovskite phase. Nevertheless, the overall crystallinity was well maintained without much structural degradation, indicating that topotactic phase control can be a useful tool to control the physical properties repeatedly via redox reactions.

• OSTI ID: 22492224
• Journal Information: AIP Advances, Vol. 5, Issue 12; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
CATALYSTS
CRITICAL TEMPERATURE
ENERGY STORAGE
EPITAXY
INDIUM COMPLEXES
LASER RADIATION
MAGNETIC PROPERTIES
MAGNETISM
MICROSTRUCTURE
OXIDATION
PEROVSKITE
PHASE TRANSFORMATIONS
REDOX REACTIONS
STRAINS
STRONTIUM COMPOUNDS
THIN FILMS