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In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films

[Image: see text] The further development of solid oxide fuel and electrolysis cells (SOFC/SOEC) strongly relies on research activities dealing with electrode materials. Recent studies showed that under operating conditions many perovskite-type oxide electrodes are prone to changes of their surface...

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Autores principales: Rupp, Ghislain M., Kubicek, Markus, Opitz, Alexander K., Fleig, Jürgen
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2018
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6158676/
https://www.ncbi.nlm.nih.gov/pubmed/30272051
http://dx.doi.org/10.1021/acsaem.8b00586
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author Rupp, Ghislain M.
Kubicek, Markus
Opitz, Alexander K.
Fleig, Jürgen
author_facet Rupp, Ghislain M.
Kubicek, Markus
Opitz, Alexander K.
Fleig, Jürgen
author_sort Rupp, Ghislain M.
collection PubMed
description [Image: see text] The further development of solid oxide fuel and electrolysis cells (SOFC/SOEC) strongly relies on research activities dealing with electrode materials. Recent studies showed that under operating conditions many perovskite-type oxide electrodes are prone to changes of their surface composition, leading to severe changes of their electrochemical performance. This results in a large scatter of data in literature and complicates comparison of materials. Moreover, little information is available on the potentially excellent properties of surfaces immediately after preparation, that is, before any degradation by exposure to other gas compositions or temperature changes. Here, we introduce in situ impedance spectroscopy during pulsed laser deposition (IPLD) as a new method for electrochemical analysis of mixed ionic and electronic conducting (MIEC) thin films during growth. First, this approach can truly reveal the properties of as-prepared MIEC electrode materials, since it avoids any alterations of their surface between preparation and investigation. Second, the measurements during growth give information on the thickness dependence of film properties. This technique is applied to La(0.6)Sr(0.4)CoO(3−δ) (LSC), one of the most promising SOFC/SOEC oxygen electrode material. From the earliest stages of LSC film deposition on yttria-stabilized zirconia (YSZ) to a fully grown thin film of 100 nm thickness, data are gained on the oxygen exchange kinetics and the defect chemistry of LSC. A remarkable reproducibility is found in repeated film growth experiments, not only for the bulk related chemical capacitance but also for the surface related polarization resistance (±10%). Polarization resistances of as-prepared LSC films are extraordinarily low (2.0 Ω cm(2) in 40 μbar O(2) at 600 °C). LSC films on YSZ and on La(0.95)Sr(0.05)Ga(0.95)Mg(0.05)O(3−δ) (LSGM) single crystals exhibit significantly different electrochemical properties, possibly associated with the tensile strain of LSC on LSGM.
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spelling pubmed-61586762018-09-28 In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films Rupp, Ghislain M. Kubicek, Markus Opitz, Alexander K. Fleig, Jürgen ACS Appl Energy Mater [Image: see text] The further development of solid oxide fuel and electrolysis cells (SOFC/SOEC) strongly relies on research activities dealing with electrode materials. Recent studies showed that under operating conditions many perovskite-type oxide electrodes are prone to changes of their surface composition, leading to severe changes of their electrochemical performance. This results in a large scatter of data in literature and complicates comparison of materials. Moreover, little information is available on the potentially excellent properties of surfaces immediately after preparation, that is, before any degradation by exposure to other gas compositions or temperature changes. Here, we introduce in situ impedance spectroscopy during pulsed laser deposition (IPLD) as a new method for electrochemical analysis of mixed ionic and electronic conducting (MIEC) thin films during growth. First, this approach can truly reveal the properties of as-prepared MIEC electrode materials, since it avoids any alterations of their surface between preparation and investigation. Second, the measurements during growth give information on the thickness dependence of film properties. This technique is applied to La(0.6)Sr(0.4)CoO(3−δ) (LSC), one of the most promising SOFC/SOEC oxygen electrode material. From the earliest stages of LSC film deposition on yttria-stabilized zirconia (YSZ) to a fully grown thin film of 100 nm thickness, data are gained on the oxygen exchange kinetics and the defect chemistry of LSC. A remarkable reproducibility is found in repeated film growth experiments, not only for the bulk related chemical capacitance but also for the surface related polarization resistance (±10%). Polarization resistances of as-prepared LSC films are extraordinarily low (2.0 Ω cm(2) in 40 μbar O(2) at 600 °C). LSC films on YSZ and on La(0.95)Sr(0.05)Ga(0.95)Mg(0.05)O(3−δ) (LSGM) single crystals exhibit significantly different electrochemical properties, possibly associated with the tensile strain of LSC on LSGM. American Chemical Society 2018-08-20 2018-09-24 /pmc/articles/PMC6158676/ /pubmed/30272051 http://dx.doi.org/10.1021/acsaem.8b00586 Text en Copyright © 2018 American Chemical Society This is an open access article published under a Creative Commons Attribution (CC-BY) License (http://pubs.acs.org/page/policy/authorchoice_ccby_termsofuse.html) , which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.
spellingShingle Rupp, Ghislain M.
Kubicek, Markus
Opitz, Alexander K.
Fleig, Jürgen
In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films
title In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films
title_full In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films
title_fullStr In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films
title_full_unstemmed In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films
title_short In Situ Impedance Analysis of Oxygen Exchange on Growing La(0.6)Sr(0.4)CoO(3−δ) Thin Films
title_sort in situ impedance analysis of oxygen exchange on growing la(0.6)sr(0.4)coo(3−δ) thin films
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6158676/
https://www.ncbi.nlm.nih.gov/pubmed/30272051
http://dx.doi.org/10.1021/acsaem.8b00586
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