Defect structure and defect-induced expansion of doped perovskite La0.7Sr0.3Co0.9Fe0.1O3-delta / Zuev A. Yu.,Sereda V. V.,Tsvetkov D. S. // INTERNATIONAL JOURNAL OF HYDROGEN ENERGY. - 2014. - V. 39, l. 36. - P. 21553-21560.

ISSN/EISSN:

0360-3199 / 1879-3487

Type:

Article

Abstract:

The results of chemical expansion measured as a function of oxygen partial pressure, pO(2), and temperature by means of dilatometric technique are presented for the perovskite-type doped cobaltite La0.7Sr0.3Co0.9Fe0.1O3-delta. The modeling of the defect structure of this perovskite was carried out. Within the framework of the model all iron sites are assumed to be occupied by localized holes whereas both electrons and holes can be localized on cobalt sites in La0.7Sr0.3Co0.9Fe0.1O3-delta. The defect structure model proposed was shown to fit perfectly well available experimental data on oxygen nonstoichiometry of the perovskite studied. Equilibrium constants of the appropriate defects reactions were, therefore, determined and concentrations of all defect species defined within the framework of the model proposed were calculated as functions of temperature and oxygen nonstoichiometry. These concentrations were employed in the chemical expansion model derived by us earlier in order to compute the chemical expansion of the La0.7Sr0.3Co0.9Fe0.1O3-delta lattice as a function of its oxygen nonstoichiometry. Cobalt ions transition from low spin (LS) state to high spin (HS) one induced by temperature increase was taken into account as well. The model proposed was shown to coincide completely with experimental data on chemical expansion for the La0.7Sr0.3Co0.9Fe0.1O3-delta at all temperatures investigated. As a result, the spin state distribution of cobalt was calculated depending on temperature for the oxide studied. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Author keywords:

Chemical expansion; Defect structure; MIEC; Oxygen nonstoichiometry; Thermal expansion; Perovskite COBALT IRON-OXIDE; LANTHANUM COBALTITES; OXYGEN NONSTOICHIOMETRY; ELECTRICAL-PROPERTIES; LA1-XSRXCO1-YFEYO3; EQUILIBRIA

DOI:

10.1016/j.ijhydene.2014.09.115

Web of Science ID:

ISI:000347576200074

Соавторы в МНС:

Другие поля

Поле	Значение
Month	DEC 12
Publisher	PERGAMON-ELSEVIER SCIENCE LTD
Address	THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
Language	English
EISSN	1879-3487
Keywords-Plus	COBALT IRON-OXIDE; LANTHANUM COBALTITES; OXYGEN NONSTOICHIOMETRY; ELECTRICAL-PROPERTIES; LA1-XSRXCO1-YFEYO3; EQUILIBRIA
Research-Areas	Chemistry; Electrochemistry; Energy \& Fuels
Web-of-Science-Categories	Chemistry, Physical; Electrochemistry; Energy \& Fuels
Author-Email	dmitry.tsvetkov@urfu.ru
ResearcherID-Numbers	Zuev, Andrey/E-6220-2014 Tsvetkov, Dmitry/N-2491-2016 Sereda, Vladimir/J-9810-2014
ORCID-Numbers	Sereda, Vladimir/0000-0002-1420-2573
Funding-Acknowledgement	Centers of Excellence Program at Ural Federal University, Russia; Ministry of Education and Science of Russian Federation {[}4.1039.2014/K]
Funding-Text	This work was supported by the Centers of Excellence Program at Ural Federal University, Russia and by the Ministry of Education and Science of Russian Federation (the State Task No. 4.1039.2014/K).
Number-of-Cited-References	24
Usage-Count-Last-180-days	2
Usage-Count-Since-2013	19
Journal-ISO	Int. J. Hydrog. Energy
Doc-Delivery-Number	AY4WP