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Synthesis and Characterization of Gd(1−x)SrxCo(1−y)FeyO(3−Δ) as a Cathode Material for Intermediate Temperature Solid Oxide Fuel Cells

Published online by Cambridge University Press:  26 February 2011

C. R. Dyck ,
G. Yu  and
V. D. Krstic
C. R. Dyck
Affiliation:
Dept. of Mechanical Engineering, Nicol Hall, Queen's University, Kingston, ON, K7L 3N6, Canada
G. Yu
Affiliation:
Dept. of Mechanical Engineering, Nicol Hall, Queen's University, Kingston, ON, K7L 3N6, Canada
V. D. Krstic
Affiliation:
Dept. of Mechanical Engineering, Nicol Hall, Queen's University, Kingston, ON, K7L 3N6, Canada
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Abstract

Gd(1−x)SrxCoO(3−Δ) (GSC) is a promising cathode material system for use in IT-SOFCs due to its high catalytic activity for oxygen reduction and appreciable conductivity. However, it has a high thermal expansion coefficient that is unmatched to the common IT-SOFC electrolyte material, Ce0.8Gd0.2O(2−Δ) (CGO). Gd0.8Sr0.2CoO(3−Δ) (GS20C) was determined to provide the best balance of properties as a base composition in the GSC system for further study. GS20C exhibited electrical conductivity of 400 S cm−1 at 600°C and a linear thermal expansion coefficient of 23 ppm/°C. Manipulation of the Co-site in GS20C by Fe substitution to form Gd(0.8)Sr(0.2)Co(1−y)FeyO(3−Δ) (GS20CFY, Y= 0, 20, 40, 60, 80, 100 atomic%) resulted in a dramatic decrease in the thermal expansion coefficient to a level close to that of the electrolyte (∼13 ppm/°C). However, the decrease in thermal expansion was accompanied by a large decrease in the conductivity as the iron content was increased in the system (to ∼10 S cm−1). Alternatively, formation of GS20C/CGO composite cathodes resulted in thermal matching with the electrolyte material up to the IT-SOFC operating temperature of approximately 600°C with the maintenance of high electrical conductivity. Composite GS20C/CGO cathodes may reduce the problems associated with poor GSC thermal matching to the electrolyte without compromising other important cathodic properties.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 801: Symposium BB – Materials and Technologies for a Hydrogen Economy , 2003 , BB3.4
Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

1. Minh, N.Q., J. Am. Cer. Soc. 76 [3], 563 (1993).Google Scholar
2. Xia, C., Rauch, W., Chen, F., and Liu, M., Solid State Ionics 149, 11 (2002).Google Scholar
3. Ohno, Y., Nagata, S., and Sato, H., Solid State Ionics 9/10, 1001 (1983).Google Scholar
4. Takeda, Y., Ueno, H., Imanishi, N., Yamamoto, O., Sammes, N., and Phillipps, M.B., Solid State Ionics 86–88, 1187 (1996).Google Scholar
5. Tai, L.-W., Nasrallah, M.M., Anderson, H.U., Sparlin, D.M., and Sehlin, S.R., Solid State Ionics 76, 259 (1995).Google Scholar
6. Chick, L.A., Pederson, L.R., Maupin, G.D., Bates, J.L., Thomas, L.E., and Exarhos, G.J., Mat. Lett. 10, 6 (1990).Google Scholar
7. Blank, D.H.A., Kruidhof, H., Flokstra, J., J. Phys. D 21, 226 (1988).Google Scholar
9. Tai, L.W., Nasrallah, M.M., Anderson, H.U., Sparlin, D.M., and Sehlin, S.R., Solid State Ionics 76, 259 (1995).Google Scholar
10. Hammou, A. and Guindet, J. in The CRC Handbook of Solid State Electrochemistry: Chapter 12 – Solid Oxide Fuel Cells, edited by Gellings, P.J. and Bouwmeester, H.J.M., (New York: CRC Press, 1997).Google Scholar