SOFC Cathode Mechanisms

Torben Jacobsen, Birgit Zachau-Christiansen, Lasse Bay, Steen Skaarup

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review

Abstract

The transient response of SOFC oxygen cathodes shows a characteristic inductive hysteresis and correspondingly the impedance diagram combines one or two capacitive arcs with a low frequency inductive arc. These features are discussed on the basis of a three step reaction sequence taken from litterature. It is argued that this kind of mechanism can only partly explain the experimental observations. The capacitive part of the low frequency response at anodic potentials is shown to be due to gas enclosures at the lectrode-electrolyte interface. As to the inductive activation mechanism of the reaction no explanation is found. The analysis indicates that the phenomenon is caused by a reaction which is not a step in the reaction sequence, but running in parallel to the oxygen reaction,thus modifying the electrocatalytic or transport properties of the electrode-electrolyte interface.
Original languageEnglish
Title of host publicationProceedings th 17th Risoe Int. Symp. on Materials Science: High Temperature Electrochemistry: Ceramics and Metals.
Place of PublicationRoskilde, Denmark
PublisherRisø National Laboratory
Publication date1996
Pages29-40
Publication statusPublished - 1996
Event17th Risoe Int. Symp. on Materials Science: High Temperature Electrochemistry: Ceramics and Metals. - Risoe, Roskilde, Denmark
Duration: 1 Jan 1996 → …

Conference

Conference17th Risoe Int. Symp. on Materials Science: High Temperature Electrochemistry: Ceramics and Metals.
CityRisoe, Roskilde, Denmark
Period01/01/1996 → …

Cite this