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Title: Linking Initial Microstructure to ORR Related Property Degradation in SOFC Cathode: A Phase Field Simulation

Abstract

Microstructure evolution driven by thermal coarsening is an important factor for the loss of oxygen reduction reaction rates in SOFC cathode. In this work, the effect of an initial microstructure on the microstructure evolution in SOFC cathode is investigated using a recently developed phase field model. Specifically, we tune the phase fraction, the average grain size, the standard deviation of the grain size and the grain shape in the initial microstructure, and explore their effect on the evolution of the grain size, the density of triple phase boundary, the specific surface area and the effective conductivity in LSM-YSZ cathodes. It is found that the degradation rate of TPB density and SSA of LSM is lower with less LSM phase fraction (with constant porosity assumed) and greater average grain size, while the degradation rate of effective conductivity can also be tuned by adjusting the standard deviation of grain size distribution and grain aspect ratio. The implication of this study on the designing of an optimal initial microstructure of SOFC cathodes is discussed.

Authors:
ORCiD logo [1];  [2];  [1]
  1. National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV (United States). Albany Research Center (ARC)
  2. National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV (United States). Albany Research Center (ARC); AECOM, Albany, OR (United States)
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV (United States). AECOM, Albany Research, OR (United States) Center (ARC), Albany, OR (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1366430
Report Number(s):
NETL-PUB-21101
Journal ID: ISSN 0013-4651
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of the Electrochemical Society
Additional Journal Information:
Journal Volume: 164; Journal Issue: 10; Journal ID: ISSN 0013-4651
Publisher:
The Electrochemical Society
Country of Publication:
United States
Language:
English
Subject:
25 ENERGY STORAGE

Citation Formats

Lei, Y., Cheng, T. -L., and Wen, Y. H. Linking Initial Microstructure to ORR Related Property Degradation in SOFC Cathode: A Phase Field Simulation. United States: N. p., 2017. Web. doi:10.1149/2.0101710jes.
Lei, Y., Cheng, T. -L., & Wen, Y. H. Linking Initial Microstructure to ORR Related Property Degradation in SOFC Cathode: A Phase Field Simulation. United States. doi:10.1149/2.0101710jes.
Lei, Y., Cheng, T. -L., and Wen, Y. H. Wed . "Linking Initial Microstructure to ORR Related Property Degradation in SOFC Cathode: A Phase Field Simulation". United States. doi:10.1149/2.0101710jes. https://www.osti.gov/servlets/purl/1366430.
@article{osti_1366430,
title = {Linking Initial Microstructure to ORR Related Property Degradation in SOFC Cathode: A Phase Field Simulation},
author = {Lei, Y. and Cheng, T. -L. and Wen, Y. H.},
abstractNote = {Microstructure evolution driven by thermal coarsening is an important factor for the loss of oxygen reduction reaction rates in SOFC cathode. In this work, the effect of an initial microstructure on the microstructure evolution in SOFC cathode is investigated using a recently developed phase field model. Specifically, we tune the phase fraction, the average grain size, the standard deviation of the grain size and the grain shape in the initial microstructure, and explore their effect on the evolution of the grain size, the density of triple phase boundary, the specific surface area and the effective conductivity in LSM-YSZ cathodes. It is found that the degradation rate of TPB density and SSA of LSM is lower with less LSM phase fraction (with constant porosity assumed) and greater average grain size, while the degradation rate of effective conductivity can also be tuned by adjusting the standard deviation of grain size distribution and grain aspect ratio. The implication of this study on the designing of an optimal initial microstructure of SOFC cathodes is discussed.},
doi = {10.1149/2.0101710jes},
journal = {Journal of the Electrochemical Society},
number = 10,
volume = 164,
place = {United States},
year = {Wed Jul 05 00:00:00 EDT 2017},
month = {Wed Jul 05 00:00:00 EDT 2017}
}

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