Revisiting the thermal and chemical expansion and stability of La0.6Sr0.4FeO3−

de Leeuwe, Christopher; Hu, Wenting; Neagu, Dragos; Papaioannou, Evangelos I.; Pramana, Stevin; Ray, Brian; Evans, John S.O.; Metcalfe, Ian S.

Abstract

The thermal and chemical expansivity of La1-xSrxFeO3-δ (x ​= ​0.4) was measured using in situ powder neutron and synchrotron X-ray diffraction at temperatures between 932 ​K and 1170 ​K and oxygen partial pressures, , between 10−19 ​bar and 0.1 ​bar, giving a wide range of oxygen non-stoichiometry from δ 0.05 to 0.22. Changes in δ were measured independently using gas analysis. This and temperature range covers the material’s use as a chemical looping oxygen carrier, a sensor material and in solid oxide fuel cells. Thermal and chemical expansivities were found to be dependent on the oxygen non-stoichiometry, δ. For δ ​< ​0.2 and T ​= ​932–1050 ​K, the linear thermal expansivity was 5.72(4) ​× ​10−5 ​Å/K and the linear chemical expansivity was 0.144(9) Å per unit change in δ. For δ ​> ​0.2 and T ​= ​973–1173 ​K, the linear thermal expansivity increases to 6.18(8) ​× ​10−5 ​Å/K. For δ ​> ​0.2, the linear chemical expansivity varies with both δ and temperature.

Citation

de Leeuwe, C., Hu, W., Neagu, D., Papaioannou, E. I., Pramana, S., Ray, B., Evans, J. S., & Metcalfe, I. S. (2021). Revisiting the thermal and chemical expansion and stability of La0.6Sr0.4FeO3−. Journal of Solid State Chemistry, 293, Article 121838. https://doi.org/10.1016/j.jssc.2020.121838

• Journal Article Type: Article
• Acceptance Date: Oct 26, 2020
• Online Publication Date: Nov 6, 2020
• Publication Date: 2021-01
• Deposit Date: Nov 26, 2020
• Publicly Available Date: Nov 30, 2021
• Journal: Journal of Solid State Chemistry
• Print ISSN: 0022-4596
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 293
• Article Number: 121838
• DOI: https://doi.org/10.1016/j.jssc.2020.121838
• Public URL: https://durham-repository.worktribe.com/output/1284748