Oxygen nonstoichiometry and defect structure of the double perovskite GdBaCo2O6-delta / Tsvetkov D. S.,Sereda V. V.,Zuev A. Yu. // SOLID STATE IONICS. - 2010. - V. 180, l. 40. - P. 1620-1625.

ISSN/EISSN:

0167-2738 / нет данных

Type:

Article

Abstract:

The results of oxygen nonstoichiometry, delta, measured by means of coulometric technique as a function of oxygen partial pressure, po(2) in temperature range 900 <= T degrees C <= 1050 are presented for GdBaCo2O6-delta with double perovskite structure. Partial molar enthalpy and entropy of oxygen in GdBaCo2O6-delta structure were calculated. Both thermodynamic properties were shown to increase dramatically in the vicinity of the oxygen nonstoichiometry value equal to 1. The po(2), dependences of oxygen nonstoichiometry and the delta dependences of the partial molar properties were found to have inflections when the oxygen content of GdBaCo2O6-delta is equal to 5.0 exactly. The modeling of the defect structure of the double perovskite GdBaCo2O6-delta was carried out by considering different reference states. Only the model based on the cubic perovskite GdCoO3 as a reference state was shown to fit the experimental data on oxygen nonstoichiometry of GdBaCo2O6-delta good enough. Equilibrium constants of the appropriate detects reactions were, therefore, determined. Concentrations of all defect species defined within the framework of this model were calculated as functions of temperature and oxygen nonstoichiometry. Oxygen vacancies were shown to be formed during po(2) diminution in gas environment in the layers of GdBaCo2O6-delta crystal lattice where they are ordered until oxygen nonstoichiometry of the oxide becomes equal to unity afterwards oxygen vacancies are formed randomly in oxygen polyhedrons. (C) 2009 Elsevier B.V. All rights reserved.

Author keywords:

Oxygen nonstoichiometry; Double perovskite; Defect structure; Partial molar quantities; Coulometric titration DOPED LANTHANUM COBALTITES; OXIDE FUEL-CELLS; CATHODES; LNBACO(2)O(5+DELTA)

DOI:

10.1016/j.ssi.2009.10.014

Web of Science ID:

ISI:000275210700003

Соавторы в МНС:

Другие поля

Поле	Значение
Month	JAN 29
Publisher	ELSEVIER SCIENCE BV
Address	PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
Language	English
Keywords-Plus	DOPED LANTHANUM COBALTITES; OXIDE FUEL-CELLS; CATHODES; LNBACO(2)O(5+DELTA)
Research-Areas	Chemistry; Physics
Web-of-Science-Categories	Chemistry, Physical; Physics, Condensed Matter
Author-Email	andrew.zuev@usu.ru
ResearcherID-Numbers	Zuev, Andrey/E-6220-2014 Tsvetkov, Dmitry/N-2491-2016 Sereda, Vladimir/J-9810-2014 Albe, Karsten/F-1139-2011
ORCID-Numbers	Sereda, Vladimir/0000-0002-1420-2573
Funding-Acknowledgement	Russian Foundation for Basic Research {[}07-03-00840a]
Funding-Text	This work was supported by the Russian Foundation for Basic Research (Grant No. 07-03-00840a) and Russian Federal Agency for Education.
Number-of-Cited-References	13
Usage-Count-Last-180-days	3
Usage-Count-Since-2013	36
Journal-ISO	Solid State Ion.
Doc-Delivery-Number	564JR