Abstract
One of the major goals in the research field of solid oxide fuel cells (SOFCs) is the development of cost-effective component materials for intermediate operating temperatures (600-800°C) [1]. In this connection, mixed ionic-electronic conductors based on LaFeO3 have attracted keen interest. Compositions from the series
La1-xMxFeO3 (M=Sr, Ca) demonstrated superior electrochemical properties as well as adjustable thermal expansion coefficients. For example La1-xCaxFeO3 (LCF) has been studied as potential SOFC cathode, catalyst for methane combustion and oxygen sensor [2-5].
In the present study, LCF powder was synthesized via a glycine-nitrate-process. The microstructure, thermal expansion coefficient, electrical conductivity and oxygen exchange properties were characterized. The calcined powder showed a broad bimodal particle size distribution due to the agglomeration of the smaller particles. After ball milling, a submicron monomodal particle size distribution was achieved. The fine powder was pressed and a sinter curve in ambient air was recorded. The thermal expansion coefficient of sintered LCF was measured in the p(O2)-range from 1 to
1×10-3 bar. The resulting values are in good agreement with those of Ce0.9Gd0.1O2 (CGO) [6] which is frequently applied as solid electrolyte material in SOFCs. The results indicate that LCF is a promising SOFC cathode material for application in the intermediate temperature range.
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[1] S. C. Singhal, Solid State Ionics 2002, 152–153, 405-410.
[2] A. Mai, et.al., Solid State Ionics 2005, 176, 1341-1350.
[3] P. Ciambelli, et.al., Applied Catalysis B: Environmental 2001, 33, 193-203.
[4] L. B. Kong, Y. S. Shen, Sensors and Actuators B: Chemical 1996, 30, 217-221.
[5] M. H. Hung, M. V. M. Rao, D.S. Tsai, Materials Chemistry and Physics 2007, 101, 297-302.
[6] S. J. Hong, A. V. Virkar, J. Am. Ceram. Soc. 1995, 78, 433-439.
Originalsprache | Englisch |
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Publikationsstatus | Veröffentlicht - 21 Sept. 2015 |
Veranstaltung | 16. Österreichische Chemietage - Innsbruck, Österreich Dauer: 21 Sept. 2015 → 24 Sept. 2015 |
Konferenz
Konferenz | 16. Österreichische Chemietage |
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Land/Gebiet | Österreich |
Ort | Innsbruck |
Zeitraum | 21/09/15 → 24/09/15 |