Titelangaben
Zheng, Yingjing ; Sauter, Ulrich ; Oehler, Gudrun ; Streeb, Martin ; Moos, Ralf:
Identification of Oxygen Exchange Mechanisms on Geometrically Defined Pt|YSZ Electrodes.
2014
Veranstaltung: 65th Annual Meeting of the International Society of Electrochemistry
, 31.08.-05.09.2014
, Lausanne, Switzerland.
(Veranstaltungsbeitrag: Kongress/Konferenz/Symposium/Tagung
,
Sonstige
Präsentationstyp)
Abstract
For application areas like fuel cells, oxygen sensors, or catalysis, the electrode system oxygen|platinum|yttria stabilized zirconia (YSZ) is still of great importance today, either as model system or as irreplaceable material system for applications in harsh environments. Until now research has been limited to (a) thick film porous electrodes, which are close to application materials, but difficult to define and to reproduce, and (b) thin film electrodes, which may have different properties than electrodes in real applications. In order to overcome this material gap, we investigated thick film model electrodes with defined geometry but without open porosity in this work.
The electrode morphology was characterized with scanning electron microscopy (SEM), focused ion beam (FIB) and FIB-SEM for 3D reconstruction. Electrochemical impedance spectroscopy (EIS) was performed for varying electrode morphology, temperature and oxygen partial pressure. In order to identify the processes in the EIS spectra, the results are compared with a physicochemical model, originally based on a work by Mitterdorfer. It includes processes like adsorption, diffusion and charge transfer. Ionic conduction and double layer capacitance have been added to the model. Furthermore, the influence of surface coverage has been taken into account. Still, not all phenomena observed in experiments could be explained by this currently accepted model. Therefore, further possible mechanisms are presented in this work.
Weitere Angaben
Publikationsform: | Veranstaltungsbeitrag (Sonstige) |
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Begutachteter Beitrag: | Ja |
Institutionen der Universität: | Fakultäten > Fakultät für Ingenieurwissenschaften Fakultäten > Fakultät für Ingenieurwissenschaften > Lehrstuhl Funktionsmaterialien > Lehrstuhl Funktionsmaterialien - Univ.-Prof. Dr.-Ing. Ralf Moos Fakultäten Fakultäten > Fakultät für Ingenieurwissenschaften > Lehrstuhl Funktionsmaterialien Profilfelder > Advanced Fields > Neue Materialien Forschungseinrichtungen > Forschungszentren > Bayreuther Materialzentrum - BayMAT Profilfelder Profilfelder > Advanced Fields Forschungseinrichtungen Forschungseinrichtungen > Forschungszentren |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 600 Technik, Medizin, angewandte Wissenschaften > 620 Ingenieurwissenschaften |
Eingestellt am: | 11 Mai 2015 12:25 |
Letzte Änderung: | 15 Apr 2016 07:27 |
URI: | https://eref.uni-bayreuth.de/id/eprint/13167 |