Oxygen Nonstoichiometry and Electrochemical Properties of GdBaCo2-xFexO6-delta Double Perovskite Cathodes / Tsvetkov Dmitry S.,Saricheva Nadezhda S.,Sereda Vladimir V.,Zuev Andrey Yu. // JOURNAL OF FUEL CELL SCIENCE AND TECHNOLOGY. - 2011. - V. 8, l. 4.

ISSN/EISSN:

1550-624X / нет данных

Type:

Article

Abstract:

Mixed ionic- and electronic-conducting perovskite-type oxides are the state-of-the-art materials for high-temperature solid-state electrochemical devices such as solid oxide fuel cells (SOFCs), oxygen membranes, and sensors. Many of such materials are cobaltite-based oxides. Recently, double perovskites REBaCo2O5.5 +/-delta, where RE is a trivalent rare earth and the oxygen content delta varies in wide range, have received a great attention as attractive materials for such application. Many interesting phenomena, such as giant magnetoresistance, charge ordering, and metal-insulator transition, have been observed in these compounds. Powder samples of GdBaCo2 xFexO6 (delta)(x = 0; 0.2) were synthesized by glycerol-nitrate method. Oxygen nonstoichiomentry of oxides GdBaCo2-xFexO6-delta (x = 0; 0.2) was measured by the thermogravimetric (TG) method as a function of temperature in the range of 25-1100 degrees C in air. Total conductivity of aforementioned oxides was studied by the four-probe dc-method as a function of temperature in the range of 25-1100 degrees C in air. Polarization resistance of double perovskite cathodes was investigated by impedance spectroscopy in symmetrical cell of the type electrode|electrolyte|electrode. ``Metal-insulator{''} transition was found at 80 degrees C in GdBaCo2O6-delta, whereas it was not observed in iron-doped sample GdBaCo1.8Fe0.2O6-delta due to the increase in oxygen content upon Fe-doping. At high temperatures, both double perovskites have almost the same total conductivity. Chemical interaction was found to decrease the performance of GdBaCo2-xFexO6-delta cathodes in YSZ-based SOFCs due to the chemical interaction between electrolyte and cathode materials, which significantly increases their polarization resistance. Behavior of total conductivity of oxides GdBaCo2-xFexO6--delta (x = 0; 0.2) with temperature was explained by assuming small polar-on charge transfer. The particularity of the latter is larger mobility of electron holes as compared with that of electrons. Increase in cathode performance was shown in the case of YSZ covered by the Ce0.8Sm0.2O2 layer in comparison with pure Zr0.9Y0.1O2 electrolyte. {[}DOI: 10.1115/1.4003631]

Author keywords:

solid oxide fuel cells; double perovskite; oxygen nonstoichiometry; electrical conductivity; polarization resistance GDBACO2O5+X LAYERED PEROVSKITE; TRANSITION

DOI:

10.1115/1.4003631

Web of Science ID:

ISI:000289118000006

Соавторы в МНС:

Другие поля

Поле	Значение
Month	AUG
Publisher	ASME-AMER SOC MECHANICAL ENG
Address	THREE PARK AVE, NEW YORK, NY 10016-5990 USA
Language	English
Article-Number	041006
Keywords-Plus	GDBACO2O5+X LAYERED PEROVSKITE; TRANSITION
Author-Email	dmitrii.tsvetkov@usu.ru
ResearcherID-Numbers	Tsvetkov, Dmitry/N-2491-2016 Zuev, Andrey/E-6220-2014 Sereda, Vladimir/J-9810-2014
ORCID-Numbers	Sereda, Vladimir/0000-0002-1420-2573
Funding-Acknowledgement	Ministry of Education and Science of the Russian Federation
Funding-Text	This work was financially supported by the Ministry of Education and Science of the Russian Federation within the framework of Federal Program ``The scientific and scientific-education personnel of Innovative Russia{''} for 2009-2013.
Number-of-Cited-References	17
Usage-Count-Last-180-days	5
Usage-Count-Since-2013	47
Journal-ISO	J. Fuel Cell Sci. Technol.
Doc-Delivery-Number	744TS