Long-Term Cr Poisoning Effect on LSCF-GDC Composite Cathodes Sintered at Different Temperatures. Issue 9 (19th July 2016)

• Record Type: Journal Article
• Authors: Xiong, Chunyan; Taillon, Joshua A.; Pellegrinelli, Christopher; Huang, Yi-Lin; Salamanca-Riba, Lourdes G.; Chi, Bo; Jian, Li; Pu, Jian; Wachsman, Eric D.
• Is Part Of: Journal of the Electrochemical Society. Volume 163:Issue 9(2016)
• Page Start: F1091
• Page End: F1099
• Publication Date: 2016-07-19
• Subjects: cathode degradation -- cathode sintering temperature -- Chromium poisoning -- Solid Oxide Fuel Cell -- strontium compounds; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0841609jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The impact of sintering temperature on Cr-poisoning of solid oxide fuel cell (SOFC) cathodes was systematically studied. La0.6 Sr0.4 Fe0.8 Co0.2 O3-δ - Ce0.9 Gd0.1 O2-δ symmetric cells were aged at 750°C in synthetic air with the presence of Crofer 22 APU, a common high temperature interconnect, over 200 hours and electrochemical impedance spectroscopy (EIS) was used to determine the degradation process. Both the ohmic resistance (RΩ ) and polarization resistance (RP ) of LSCF-GDC cells, extracted from EIS spectra, for different sintering temperatures increase as a function of aging time. Furthermore, the Cr-related degradation rate increases with decreased cathode sintering temperature. The polarization resistance of cathode sintered at lower temperature (950°C) increases dramatically while aging with the presence of Cr and also significantly decreases the oxygen partial pressure dependence after aging. The degradation rate shows a positive correlation to the concentration of Cr. The results indicate that decreased sintering temperature increases the total surface area, leading to more available sites for Sr-Cr-O nucleation and thus greater Cr degradation.