Determination of Kinetic Parameters and Identification of the Rate-Determining Steps in the Oxygen Exchange Process for LaNi0.6Fe0.4O3−δ
Электронный научный архив УРФУ
Информация об архиве | Просмотр оригинала| Поле | Значение | |
| Заглавие |
Determination of Kinetic Parameters and Identification of the Rate-Determining Steps in the Oxygen Exchange Process for LaNi0.6Fe0.4O3−δ
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| Автор |
Porotnikova, N.
Zakharov, D. Khodimchuk, A. Kurumchin, E. Osinkin, D. |
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| Тематика |
ELECTRODE MATERIAL
LANI0.6FE0.4O3−Δ OXYGEN DIFFUSION RATE-DETERMINING STEP SURFACE IRON LANTHANUM METAL OXIDE NICKEL OXYGEN OXYGEN 18 OXIDE ARTICLE CERAMICS CHEMICAL ANALYSIS CHEMICAL INTERACTION CRYSTAL STRUCTURE DIFFUSION COEFFICIENT ISOTOPE EXCHANGE WITH GAS PHASE EQUILIBRATION ISOTOPE LABELING MATHEMATICAL MODEL OXYGEN DIFFUSION OXYGEN TENSION PARTIAL PRESSURE PULSE ISOTOPE EXCHANGE SURFACE PROPERTY DIFFUSION GAS CERAMICS DIFFUSION GASES OXIDES OXYGEN |
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| Описание |
The mixed ionic and electronic oxide LaNi0.6Fe0.4O3−δ (LNF) is a promising ceramic cathode material for solid oxide fuel cells. Since the reaction rate of oxygen interaction with the cathode material is extremely important, the present work considers the oxygen exchange mechanism between O2 and LNF oxide. The kinetic dependence of the oxygen/oxide interaction has been determined by two isotopic methods using 18O-labelled oxygen. The application of the isotope exchange with the gas phase equilibrium (IE-GPE) and the pulsed isotope exchange (PIE) has provided information over a wide range of temperatures (350–800 °C) and oxygen pressures (10–200 mbar), as each method has different applicability limits. Applying mathematical models to treat the kinetic relationships, the oxygen exchange rate (rH, atom × cm−2 × s−1) and the diffusion coefficient (D, cm2/s) were calculated. The values of rH and D depend on both temperature and oxygen pressure. The activation energy of the surface exchange rate is 0.73 ± 0.05 eV for the PIE method at 200 mbar, and 0.48 ± 0.02 eV for the IE-GPE method at 10–20 mbar; for the diffusion coefficient, the activation energy equals 0.62 ± 0.01 eV at 10–20 mbar for the IE-GPE method. Differences in the mechanism of oxygen exchange and diffusion on dense and powder samples are observed due to the different microstructure and surface morphology of the samples. The influence of oxygen pressure on the ratio of contributions of different exchange types to the total oxygen exchange rate is demonstrated. For the first time, the rate-determining step in the oxygen exchange process for LNF material has been identified. This paper discusses the reasons for the difference in the mechanisms of oxygen exchange and diffusion. © 2023 by the authors.
This research was funded by the Government Assignment No. 122020100324-3 by IHTE UB RAS. |
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| Дата |
2024-04-05T16:31:42Z
2024-04-05T16:31:42Z 2023 |
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| Тип |
Article
Journal article (info:eu-repo/semantics/article) |info:eu-repo/semantics/publishedVersion |
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| Идентификатор |
Porotnikova, N, Zakharov, D, Khodimchuk, A, Kurumchin, E & Osinkin, D 2023, 'Determination of Kinetic Parameters and Identification of the Rate-Determining Steps in the Oxygen Exchange Process for LaNi0.6Fe0.4O3−δ', International Journal of Molecular Sciences, Том. 24, № 16, 13013. https://doi.org/10.3390/ijms241613013
Porotnikova, N., Zakharov, D., Khodimchuk, A., Kurumchin, E., & Osinkin, D. (2023). Determination of Kinetic Parameters and Identification of the Rate-Determining Steps in the Oxygen Exchange Process for LaNi0.6Fe0.4O3−δ. International Journal of Molecular Sciences, 24(16), [13013]. https://doi.org/10.3390/ijms241613013 1661-6596 Final All Open Access, Gold, Green https://www.scopus.com/inward/record.uri?eid=2-s2.0-85168716338&doi=10.3390%2fijms241613013&partnerID=40&md5=07516e73c604d45146661057955b150c https://www.mdpi.com/1422-0067/24/16/13013/pdf?version=1692609108 http://elar.urfu.ru/handle/10995/130732 10.3390/ijms241613013 85168716338 001056077100001 |
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| Язык |
en
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| Права |
Open access (info:eu-repo/semantics/openAccess)
cc-by https://creativecommons.org/licenses/by/4.0/ |
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| Формат |
application/pdf
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| Издатель |
Multidisciplinary Digital Publishing Institute (MDPI)
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| Источник |
International Journal of Molecular Sciences
International Journal of Molecular Sciences |
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