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Title: Quantifying intermediate-frequency heterogeneities of SOFC electrodes using X-ray computed tomography

Abstract

The electrodes in solid oxide fuel cells (SOFCs) consist of three phases interconnected in three dimensions. The volume needed to describe quantitatively such microstructures depends on several lengths scales, which are functions of materials properties and fabrication methods. This work focuses on quantifying the volume needed to represent “intermediate frequency” heterogeneities in electrodes of a commercial SOFC using X-ray computed tomography (CT) over two different length scales. Electrode volumes of 150 x 150 x 9 μm 3 were extracted from a synchrotron-based micro-CT data set, with 13 μm 3 voxels. 13.6 x 19.8 x 19.4 μm 3 of the cathode and 26.3 x 24.8 x 15.7 μm 3 of the anode were extracted from laboratory nano-CT data sets, both with 65 3 nm 3 voxels. After comparing the variation across sub-regions for the greyscale values from the micro-CT, and for the phase fractions and triple phase boundary densities from the nano-CT, it was found that the sub-region length scales needed to yield statistically similar average values were an order of magnitude larger than those expected to capture the “high frequency” heterogeneity related to the discrete nature of the three phases in electrodes. In conclusion, the challenge of quantifying such electrodesmore » using available experimental methods is discussed.« less

Authors:
 [1];  [1];  [1];  [2];  [1];  [3];  [1]; ORCiD logo [1]
  1. Carnegie Mellon Univ., Pittsburgh, PA (United States)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
  3. National Energy Technology Lab., Morgantown, WV (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Energy Technology Laboratory (NETL); National Science Foundation (NSF)
OSTI Identifier:
1392614
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of the American Ceramic Society
Additional Journal Information:
Journal Volume: 100; Journal Issue: 5; Journal ID: ISSN 0002-7820
Publisher:
American Ceramic Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; microstructure; oxides; porous materials; solid oxide fuel cells; X-ray computed tomography

Citation Formats

Epting, William K., Mansley, Zachary, Menasche, David B., Kenesei, Peter, Suter, Robert M., Gerdes, Kirk, Litster, Shawn, and Salvador, Paul A. Quantifying intermediate-frequency heterogeneities of SOFC electrodes using X-ray computed tomography. United States: N. p., 2017. Web. doi:10.1111/jace.14775.
Epting, William K., Mansley, Zachary, Menasche, David B., Kenesei, Peter, Suter, Robert M., Gerdes, Kirk, Litster, Shawn, & Salvador, Paul A. Quantifying intermediate-frequency heterogeneities of SOFC electrodes using X-ray computed tomography. United States. doi:10.1111/jace.14775.
Epting, William K., Mansley, Zachary, Menasche, David B., Kenesei, Peter, Suter, Robert M., Gerdes, Kirk, Litster, Shawn, and Salvador, Paul A. Fri . "Quantifying intermediate-frequency heterogeneities of SOFC electrodes using X-ray computed tomography". United States. doi:10.1111/jace.14775. https://www.osti.gov/servlets/purl/1392614.
@article{osti_1392614,
title = {Quantifying intermediate-frequency heterogeneities of SOFC electrodes using X-ray computed tomography},
author = {Epting, William K. and Mansley, Zachary and Menasche, David B. and Kenesei, Peter and Suter, Robert M. and Gerdes, Kirk and Litster, Shawn and Salvador, Paul A.},
abstractNote = {The electrodes in solid oxide fuel cells (SOFCs) consist of three phases interconnected in three dimensions. The volume needed to describe quantitatively such microstructures depends on several lengths scales, which are functions of materials properties and fabrication methods. This work focuses on quantifying the volume needed to represent “intermediate frequency” heterogeneities in electrodes of a commercial SOFC using X-ray computed tomography (CT) over two different length scales. Electrode volumes of 150 x 150 x 9 μm3 were extracted from a synchrotron-based micro-CT data set, with 13 μm3 voxels. 13.6 x 19.8 x 19.4 μm3 of the cathode and 26.3 x 24.8 x 15.7 μm3 of the anode were extracted from laboratory nano-CT data sets, both with 653 nm3 voxels. After comparing the variation across sub-regions for the greyscale values from the micro-CT, and for the phase fractions and triple phase boundary densities from the nano-CT, it was found that the sub-region length scales needed to yield statistically similar average values were an order of magnitude larger than those expected to capture the “high frequency” heterogeneity related to the discrete nature of the three phases in electrodes. In conclusion, the challenge of quantifying such electrodes using available experimental methods is discussed.},
doi = {10.1111/jace.14775},
journal = {Journal of the American Ceramic Society},
number = 5,
volume = 100,
place = {United States},
year = {Fri Mar 03 00:00:00 EST 2017},
month = {Fri Mar 03 00:00:00 EST 2017}
}

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