Phase relations during water incorporation in the oxygen and proton conductor Sr6Ta2O11 / Animitsa I,Nieman A,Titova S,Kochetova N,Isaeva E,Sharafutdinov A,Timofeeva N,Colomban P // SOLID STATE IONICS. - 2003. - V. 156, l. 1-2. - P. 95-102.

ISSN/EISSN:

0167-2738 / нет данных

Type:

Article

Abstract:

Evolution of the structure and phase relations of the oxygen-deficient cryolite Sr6Ta2O11 and phase Sr5.92Ta2.08O11.12 from homogeneity range have been investigated during water intercalation by gravimetry, dilatometry and X-ray diffraction (XRD) measurements. Intercalation of H2O up to similar to 0.50 and 0.30 mol H2O per formula units Sr6Ta2O11 and Sr5.92Ta2.08 O-11.12, respectively, takes place without change of the crystal structure, which could be described under the cubic space group Fmim with a cell parameters of approximately 8.32 Angstrom. Further intercalation of water leads to structure transformation to the orthorhombic space group Fmmm. The temperature of phase transition increases with increasing pH(2)O. It is around 475-450 C at the humidity of surrounding atmosphere (pH(2)O = 0.02 atm). This phase transition is induced by pH(2)O (T= constant) and temperature (pH(2)O=constant) change and can be observed as a jump on gravimetry curves VS. pH(2)O or T. At 200 C, the most hydrated phases correspond to the compositions Sr6Ta2O11.0.96H(2)O (H20 stoichiometry close to the theoretical value of 1.0) and Sr5.92Ta2.08O11.12.0.6H(2)O (70\% of the theoretical value). A fragment of Sr6Ta2O11-H2O phase diagram is proposed. (C) 2003 Elsevier Science B.V All rights reserved.

Author keywords:

oxygen-deficient cryolite; Sr6Ta2O11; water intercalation; phase transition; crystal structure PEROVSKITE-RELATED STRUCTURE; BA2IN2O5

DOI:

10.1016/S0167-2738(02)00605-7

Web of Science ID:

ISI:000180785200010

Соавторы в МНС:

Другие поля

Поле	Значение
Month	JAN
Publisher	ELSEVIER SCIENCE BV
Address	PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
Language	English
Article-Number	PII S0167-2738(02)00605-7
Keywords-Plus	PEROVSKITE-RELATED STRUCTURE; BA2IN2O5
Research-Areas	Chemistry; Physics
Web-of-Science-Categories	Chemistry, Physical; Physics, Condensed Matter
ResearcherID-Numbers	Titova, Svetlana/D-2316-2013
Number-of-Cited-References	21
Usage-Count-Since-2013	6
Journal-ISO	Solid State Ion.
Doc-Delivery-Number	642BV