Mixed conductivity, Mossbauer spectra and thermal expansion of (La,Sr)(Fe,Ni)O3-delta perovskites / Tsipis E. V.,Kiselev E. A.,Kolotygin V. A.,Waerenborgh J. C.,Cherepanov V. A.,Kharton V. V. // SOLID STATE IONICS. - 2008. - V. 179, l. 38. - P. 2170-2180.

ISSN/EISSN:

0167-2738 / нет данных

Type:

Article

Abstract:

The incorporation of Sr2+ in perovskite-type La1-ySryFe1-xNixO3-delta increases oxygen deficiency and ionic transport at elevated temperatures, but leads to a lower thermodynamic stability as reflected by narrowing the solid-solution domain at 1373 K down to x approximate to 0.25 at y = 0.10 and x approximate to 0.12 at y = 0.20 in air. The average thermal expansion coefficients of La1-ySryFe1-xNixO3-delta (x = 0.1-0.4, y = 0.1-0.2) ceramics vary in the ranges (12.4-13.4)x 10(-6) K-1 at 700-1150 K and(14.2-18.0) x 10(-6) K-1 at 1150-1370 K, rising with strontium and nickel contents. These additives lower also the temperature of orthorhombic -> rhombohedral phase transition visible in the dilatometric curves, promote hole delocalization, increase total conductivity and decrease Seebeck coefficient Studied in the oxygen partial pressure range from 10(-5) to 0.4 atm at 973-1223 K. The steady-state oxygen permeation fluxes through single-phase La1-ySryFe1-xNixO3-delta (x = 0.1-0.2. y = 0.1-0.2) membranes, with an activation energy of 206-235 kJ/mol, are determined by both surface-exchange and bulk ionic conduction limited by the oxygen-vacancy concentration. Doping with nickel has a weak negative effect on the oxygen transport, probably due to defect cluster formation involving the vacancies and Ni2+. On the contrary, at low temperatures when (La,Sr)(Fe,Ni)O3-delta becomes almost oxygen-stoichiometric in air, the Mossbauer spectroscopy and thermogravimetric analysis showed that the average oxidation state of nickel is higher than +3, similar to iron cations. (C) 2008 Elsevier B.V. All rights reserved.

Author keywords:

Perovskites; Mixed conductors; Ferrites-nickelates; Oxygen permeability; Phase relationships; p-Type electronic conductivity; Seebeck coefficient; Dilatometry OXIDE FUEL-CELLS; NI-O SYSTEM; CATHODE MATERIAL; ELECTROCHEMICAL CHARACTERIZATION; ELECTRICAL-CONDUCTIVITY; OXYGEN NONSTOICHIOMETRY; ELECTRONIC CONDUCTIVITY; TRANSPORT-PROPERTIES; LANTHANUM FERRITE; CRYSTAL-STRUCTURE

DOI:

10.1016/j.ssi.2008.07.017

Web of Science ID:

ISI:000262201600008

Соавторы в МНС:

Другие поля

Поле	Значение
Month	NOV 30
Publisher	ELSEVIER SCIENCE BV
Address	PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
Language	English
Keywords-Plus	OXIDE FUEL-CELLS; NI-O SYSTEM; CATHODE MATERIAL; ELECTROCHEMICAL CHARACTERIZATION; ELECTRICAL-CONDUCTIVITY; OXYGEN NONSTOICHIOMETRY; ELECTRONIC CONDUCTIVITY; TRANSPORT-PROPERTIES; LANTHANUM FERRITE; CRYSTAL-STRUCTURE
Research-Areas	Chemistry; Physics
Web-of-Science-Categories	Chemistry, Physical; Physics, Condensed Matter
Author-Email	kharton@ua.pt
ResearcherID-Numbers	Waerenborgh, Joao/C-3701-2011 Cherepanov, Vladimir/E-6451-2014 Kharton, Vladislav /P-6306-2014 Tsipis, Ekaterina/A-3590-2015 Grupo, AE/B-3302-2014
ORCID-Numbers	Waerenborgh, Joao/0000-0001-6171-4099 Cherepanov, Vladimir/0000-0003-3653-6459 Grupo, AE/0000-0002-0913-4772 Tsipis, Ekaterina/0000-0002-1458-484X
Funding-Acknowledgement	FCF, Portugal {[}PTDC/CTM/64357/2006, SFRH/BPD/28629/2006]; Russian Federal Agency on Science and Innovations {[}02.444.11.7020]
Funding-Text	This work was supported by the FCF, Portugal (projects PTDC/CTM/64357/2006 and SFRH/BPD/28629/2006), and the Russian Federal Agency on Science and Innovations (state contract No. 02.444.11.7020). Experimental assistance and helpful discussions made by S. Yakovlev, A. Yaremchenko and A. Kovalevsky, are gratefully acknowledged.
Number-of-Cited-References	44
Usage-Count-Since-2013	48
Journal-ISO	Solid State Ion.
Doc-Delivery-Number	390ZG