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Title: Reversible nano-structuring of SrCrO3-δ through oxidization and reduction at low temperatures

Abstract

Oxygen vacancies are often present in complex oxides as point defects and their effect on the electronic properties of the oxides is typically uniform and isotropic. Exploiting oxygen deficiency in order to generate controllably, novel structures and functional properties remains a challenging goal. We show that epitaxial strontium chromite films can be transformed, reversibly and at low temperature, from the cubic metallic perovskite SrCrO3-δ to the rhombohedral semiconducting SrCrO2.8. Oxygen vacancies aggregate and give rise to ordered arrays of {111}-oriented SrO2 planes interleaved between layers of tetrahedrally-coordinated Cr4+ and separated by ~1 nm. First-principle calculations provide insight into the origin of the stability of such nanostructures and, consistent with the experimental data, predict that the barrier for oxide ion diffusion along these quasi-2D nanostructures is ~5 times lower than that in the cubic SrCrO3-δ – a property of considerable importance in, for example, solid oxide fuel cells.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1170489
Report Number(s):
PNNL-SA-101384
47425; 47862; KC0203020
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Communications, 5:Artcle No. 4669
Country of Publication:
United States
Language:
English
Subject:
SrCrO3-δ; Nano-structuring; Environmental Molecular Sciences Laboratory

Citation Formats

Zhang, Hongliang, Sushko, Petr, Colby, Robert J., Du, Yingge, Bowden, Mark E., and Chambers, Scott A. Reversible nano-structuring of SrCrO3-δ through oxidization and reduction at low temperatures. United States: N. p., 2014. Web. doi:10.1038/ncomms5669.
Zhang, Hongliang, Sushko, Petr, Colby, Robert J., Du, Yingge, Bowden, Mark E., & Chambers, Scott A. Reversible nano-structuring of SrCrO3-δ through oxidization and reduction at low temperatures. United States. doi:10.1038/ncomms5669.
Zhang, Hongliang, Sushko, Petr, Colby, Robert J., Du, Yingge, Bowden, Mark E., and Chambers, Scott A. Mon . "Reversible nano-structuring of SrCrO3-δ through oxidization and reduction at low temperatures". United States. doi:10.1038/ncomms5669.
@article{osti_1170489,
title = {Reversible nano-structuring of SrCrO3-δ through oxidization and reduction at low temperatures},
author = {Zhang, Hongliang and Sushko, Petr and Colby, Robert J. and Du, Yingge and Bowden, Mark E. and Chambers, Scott A.},
abstractNote = {Oxygen vacancies are often present in complex oxides as point defects and their effect on the electronic properties of the oxides is typically uniform and isotropic. Exploiting oxygen deficiency in order to generate controllably, novel structures and functional properties remains a challenging goal. We show that epitaxial strontium chromite films can be transformed, reversibly and at low temperature, from the cubic metallic perovskite SrCrO3-δ to the rhombohedral semiconducting SrCrO2.8. Oxygen vacancies aggregate and give rise to ordered arrays of {111}-oriented SrO2 planes interleaved between layers of tetrahedrally-coordinated Cr4+ and separated by ~1 nm. First-principle calculations provide insight into the origin of the stability of such nanostructures and, consistent with the experimental data, predict that the barrier for oxide ion diffusion along these quasi-2D nanostructures is ~5 times lower than that in the cubic SrCrO3-δ – a property of considerable importance in, for example, solid oxide fuel cells.},
doi = {10.1038/ncomms5669},
journal = {Nature Communications, 5:Artcle No. 4669},
number = ,
volume = ,
place = {United States},
year = {Mon Aug 18 00:00:00 EDT 2014},
month = {Mon Aug 18 00:00:00 EDT 2014}
}
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