Long-Term Cr Poisoning Effect on LSCF-GDC Composite Cathodes Sintered at Different Temperatures [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 621.3 Electrical, magnetic, optical, communications, computer engineering; electronics, lighting
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Office of the Assistant Secretary of Energy for Fossil Energy ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2016
• Mô tả vật lý: Size: p. F1091-F1099 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 255981
• Chủ đề: 1. 30 direct energy conversion; 2. 36 materials science; 3. 37 inorganic, organic, physical, and analytical chemistry; 4. Cathode degradation; 5. Cathode sintering temperature; 6. Chromium poisoning; 7. Solid oxide fuel cell; 8. Strontium compounds

Tóm tắt

 Here, the impact of sintering temperature on Cr-poisoning of solid oxide fuel cell (SOFC) cathodes was systematically studied. La<
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  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 (R<
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 ) 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.