Investigation of the high-temperature redox chemistry of Sr2Fe1.5Mo0.5O6−δvia in situ neutron diffraction

Daniel E. Bugaris; Jason P. Hodges; Ashfia Huq; W. Michael Chance; Andreas Heyden; Fanglin Chen; Hans-Conrad zur Loye

doi:10.1039/C3TA14913G

Investigation of the high-temperature redox chemistry of Sr₂Fe_1.5Mo_0.5O_6−δvia in situ neutron diffraction†

Daniel E. Bugaris,^a Jason P. Hodges,^b Ashfia Huq,^b W. Michael Chance,^a Andreas Heyden,^c Fanglin Chen^d and Hans-Conrad zur Loye*^a

Author affiliations

* Corresponding authors

^a Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA
E-mail: zurloye@mailbox.sc.edu
Tel: +1 803 777 6916

^b Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA

^c Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, USA

^d Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208, USA

Abstract

Crystallographic structural changes were investigated for Sr₂Fe_1.5Mo_0.5O_6−δ, an electrode material for symmetric solid oxide fuel cells. The samples of this material were heated and cooled in wet hydrogen and wet oxygen atmospheres, to simulate the reducing and oxidizing conditions experienced under actual fuel cell operating conditions, and their structures and oxygen contents were determined using in situ powder neutron diffraction. The existence of a reversible tetragonal to cubic phase transition was established to occur between room temperature and 400 °C, both on heating and cooling in either oxygen or hydrogen. The oxygen content reaches a low value of 5.50(2) at 850 °C in wet hydrogen. Excellent correlations are observed between the oxygen content of the structure and the conductivities reported in the literature.

$Graphical abstract: Investigation of the high-temperature redox chemistry of Sr2Fe1.5Mo0.5O6−δvia in situ neutron diffraction$

Supplementary files

Article information

DOI: https://doi.org/10.1039/C3TA14913G
Article type: Paper
Submitted: 27 Nov 2013
Accepted: 26 Jan 2014
First published: 07 Feb 2014

Download Citation

J. Mater. Chem. A, 2014,2, 4045-4054

Author version available

Download author version (PDF)

Permissions

Request permissions

Investigation of the high-temperature redox chemistry of Sr₂Fe_1.5Mo_0.5O_6−δvia in situ neutron diffraction

D. E. Bugaris, J. P. Hodges, A. Huq, W. M. Chance, A. Heyden, F. Chen and H. Z. Loye, J. Mater. Chem. A, 2014, 2, 4045 DOI: 10.1039/C3TA14913G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Journal of Materials Chemistry A