16. Anomolus Shrinkage of Lanthanum Strontium Manganite

  1. Narottam P. Bansal
  1. Benjamin McCarthy1,
  2. Harlan Anderson1,
  3. Xaio-Dong Zhou1,
  4. Larry Pederson2,
  5. Gregory Coffey2 and
  6. Prabhakar Singh2

Published Online: 26 MAR 2008

DOI: 10.1002/9780470291245.ch16

Advances in Solid Oxide Fuel Cells: Ceramic Engineering and Science Proceedings, Volume 26, Number 4

Advances in Solid Oxide Fuel Cells: Ceramic Engineering and Science Proceedings, Volume 26, Number 4

How to Cite

McCarthy, B., Anderson, H., Zhou, X.-D., Pederson, L., Coffey, G. and Singh, P. (2005) Anomolus Shrinkage of Lanthanum Strontium Manganite, in Advances in Solid Oxide Fuel Cells: Ceramic Engineering and Science Proceedings, Volume 26, Number 4 (ed N. P. Bansal), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470291245.ch16

Author Information

  1. 1

    University of Missouri-Rolla; Rolla, MO 63129

  2. 2

    Pacific Northwest National Laboratory; Richland, WA 99352

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 2005

ISBN Information

Print ISBN: 9781574982343

Online ISBN: 9780470291245

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Keywords:

  • anomalous shrinkage;
  • lanthanum;
  • stoichiomebic;
  • shrinkage;
  • oxygen

Summary

Anomalous shrinkage behavior of porous Sr-doped lanthanum manganite (La1-xSrx)1-y MnO3+8, or LSM, where x = 0.0 to 0.4) has been studied as a function of thermal cycling, oxygen partial pressure, and Sr dopant concentration. An anomalous shrinkage due to thermal cycling in doped lanthanum manganite perovskite has previously been reported in the temperature range of 600°C to 1000°C.1,2 However, the shrinkage reported here was in a 150°C range. Shrinkage of LSM during PO2 cycling between air (2×105ppm O2) and N2 (10ppm), was much less pronounced than that of thermal cycling in the same temperature range. The two cannot be directly compared due to the difference in cycling time. The effect of Sr dopant concentration on the shrinkage due to thermal cycling reached a maximum at a dopant level of 0.1. The postulated mechanism responsible for anomalous shrinkage is the metal ion vacancy gradient produced by the oxygen nonstoichiometry of LSM. Along with this gradient or driving force for metal ion vacancy diffusion; shrinkage also requires vacancy mobility or thermal excitation to advance the anomalous shrinkage.