Phase Transitions and Phase Decomposition of La{1-x}Sr{x}CoO{3-delta} in Low Oxygen Partial Pressures

Journal Article · Tue Jan 01 04:00:00 EST 2008 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2008.03.033· OSTI ID:959923

Ovenstone, J; White, J; Misture, S

High-temperature X-ray diffraction has been used to investigate the phase stability of lanthanum strontium cobalt oxide (LSC) for a range of materials with the formula La1-xSrxCoO3-{delta} (x = 0.7, 0.4, and 0.2). The stability of LSC increases with La content in low oxygen partial pressures at high temperature. Oxygen vacancy ordering has been observed for all three compositions in either low oxygen pressure or under reducing gas, as evidenced by the formation of the brownmillerite phase. The crystal structure of the vacancy-ordered phase was determined using Rietveld analysis of synchrotron X-ray diffraction data. The decomposition products under low oxygen pressure and in reducing conditions have been identified and characterized, including the phase transition and thermal expansion of the primary decomposition products, LaSrCoO4 and LaSrCoO3.5.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 959923
• Report Number(s): BNL--82909-2009-JA
• Journal Information: Journal of Power Sources, Journal Name: Journal of Power Sources Journal Issue: 1 Vol. 181; ISSN JPSODZ; ISSN 0378-7753
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
43 PARTICLE ACCELERATORS
COBALT OXIDES
CRYSTAL STRUCTURE
LANTHANUM
OXYGEN
PARTIAL PRESSURE
PHASE STABILITY
PHASE TRANSFORMATIONS
STABILITY
STRONTIUM
SYNCHROTRONS
THERMAL EXPANSION
X-RAY DIFFRACTION
national synchrotron light source