Mechanisms of performance degradation of (La,Sr)(Co,Fe)O3-δ solid oxide fuel cell cathodes

Hongqian Wang, Kyle J. Yakal-Kremski, Ted Yeh, Ghislain M. Rupp, Andreas Limbeck, Jürgen Fleig, Scott A. Barnett

Research output: Contribution to journalArticlepeer-review

81 Scopus citations

Abstract

Symmetric cells with porous La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) electrodes on Gd0.1Ce0.9O1.95 (GDC) electrolytes were aged at 800°C for 800 hours in ambient air. Electrochemical impedance spectroscopy (EIS) measurements performed periodically at 700°C showed a continuous increase of the polarization resistance from 0.15 to 0.34 Ω · cm2. Three-dimensional (3D) tomographic analysis using focused ion beam-scanning electron microscopy (FIB-SEM) showed negligible changes due to the ageing, suggesting that the observed resistance increase was not caused by electrode morphological evolution. However, an increased amount, by a factor of 3, of a water-soluble Sr rich surface phase on the aged LSCF electrode was detected by an etching procedure coupled with inductively coupled plasma-optical emission spectrometry (ICP-OES). The electrochemical analysis in combination with the microstructural parameters determined by FIB-SEM was used to examine the effect of Sr segregation on the rate of oxygen surface exchange, based on the Adler-Lane-Steele (ALS) model.

Original languageEnglish (US)
Pages (from-to)F581-F585
JournalJournal of the Electrochemical Society
Volume163
Issue number6
DOIs
StatePublished - 2016

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Renewable Energy, Sustainability and the Environment
  • Surfaces, Coatings and Films
  • Electrochemistry
  • Materials Chemistry

Fingerprint

Dive into the research topics of 'Mechanisms of performance degradation of (La,Sr)(Co,Fe)O<sub>3-δ</sub> solid oxide fuel cell cathodes'. Together they form a unique fingerprint.

Cite this