A. D. Koryakov, O. V. Merkulov, I. A. Leonidov, A. A. Markov, O. N. Leonidova, M. V. Patrakeev
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引用次数: 0
Abstract
The structure, oxygen non-stoichiometry, thermomechanical and electrical properties of perovskite-type BaFe1−xCexO3−δ (x = 0.05, 0.10, 0.15) were studied in the light of the potential use of these oxides as electrode materials of solid oxide fuel cells. Partial substitution of iron by cerium in barium ferrite was shown to stimulate water incorporation into oxygen vacancies. This phenomenon is manifested by dehydration during heating, which is clearly registered by thermogravimetric and dilatometric measurements. Different behavior of cerium ions residing in the A- and B-sublattices of perovskite-type ferrites was revealed. In contrast to Sr1−xCexFeO3−δ oxide series, in which the concentration of Ce3+ ions under reducing conditions can exceed that of Ce4+, no signs of Ce4+ reduction were detected in BaFe1−xCexO3−δ under the same conditions. A negative influence of cerium substitution for iron on electrical conductivity was detected. The oxygen-ion conductivity of the x = 0.05 composition at 950 °C was found to be as high as 0.358 ± 0.002 S·cm−1, whereas the ion conductivity of the oxide with x = 0.10 was only 0.041 ± 0.001 S·cm−1. Such a strong suppression of oxygen transport is argued to be the result of a local lattice strain caused by a considerable difference between the sizes of cerium and iron ions. The unfavorable impact of cerium in BaFe1−xCexO3−δ on n- and p-type conductivity is attributed to its impeding role in the Fe–O–Fe electron transport network.
期刊介绍：
The Journal of Solid State Electrochemistry is devoted to all aspects of solid-state chemistry and solid-state physics in electrochemistry.
The Journal of Solid State Electrochemistry publishes papers on all aspects of electrochemistry of solid compounds, including experimental and theoretical, basic and applied work. It equally publishes papers on the thermodynamics and kinetics of electrochemical reactions if at least one actively participating phase is solid. Also of interest are articles on the transport of ions and electrons in solids whenever these processes are relevant to electrochemical reactions and on the use of solid-state electrochemical reactions in the analysis of solids and their surfaces.
The journal covers solid-state electrochemistry and focusses on the following fields: mechanisms of solid-state electrochemical reactions, semiconductor electrochemistry, electrochemical batteries, accumulators and fuel cells, electrochemical mineral leaching, galvanic metal plating, electrochemical potential memory devices, solid-state electrochemical sensors, ion and electron transport in solid materials and polymers, electrocatalysis, photoelectrochemistry, corrosion of solid materials, solid-state electroanalysis, electrochemical machining of materials, electrochromism and electrochromic devices, new electrochemical solid-state synthesis.
The Journal of Solid State Electrochemistry makes the professional in research and industry aware of this swift progress and its importance for future developments and success in the above-mentioned fields.
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