<div class="csl-bib-body">
<div class="csl-entry">Doppler, M. (2018). <i>On the electrochemistry of YSZ/Ni and related model electrodes</i> [Dissertation, Technische Universität Wien]. reposiTUm. https://doi.org/10.34726/hss.2018.33035</div>
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dc.identifier.uri
https://doi.org/10.34726/hss.2018.33035
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dc.identifier.uri
http://hdl.handle.net/20.500.12708/7669
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dc.description.abstract
Solid oxide fuel cells (SOFCs) are highly efficient and clean electrochemical energy converters capable of utilizing a wide variety of fuel infrastructures. Since anode performance is critical in determining SOFC lifetime, model anode electrodes, consisting of structured metal thin film electrodes on yttria stabilized zirconia (YSZ), are employed in this thesis to investigate the reaction mechanism for hydrogen oxidation in SOFC anodes. The main emphasis is put on YSZ/Ni as the standard anode material for SOFCs. Electrocatalytic properties were investigated with the polarization resistance measured by impedance spectroscopy. Measurements on an electrode series with varying TPB length (but constant area) showed that a part of the activity originated from the TPB. Using an electrode series with varying area (but constant TPB length) the unaccounted activity could clearly be attributed to a previously unknown area-related reaction pathway for hydrogen oxidation on YSZ/Ni electrodes. Variation of temperature, hydrogen and water partial pressures, and addition of hydrogen sulfide further solidified the proposed area pathway and showed the different chemical properties of the reaction pathways. Using experimental data two possible reaction mechanisms for the newly found area pathway were proposed. To further broaden the knowledge base for hydrogen reaction mechanisms on metal/ceramic electrocatalysts, experiments described above for YSZ/Ni were carried out for the following material combinations: YSZ/Pt, scandia doped zirconia/Ni, and titania/Ni. The results showed that both the metal and ceramic phase influence the electrochemical properties, showing that the metal phase does not merely act as a current collector. The results, combined with literature data, further indicate that catalytic activity of model electrodes is either controlled by the state of the electrolyte surface or by foreign phases in the TPB region.
en
dc.language
English
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dc.language.iso
en
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dc.rights.uri
http://rightsstatements.org/vocab/InC/1.0/
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dc.subject
solid oxide fuel cell
en
dc.subject
Impedance spectroscopy
en
dc.subject
anodes
en
dc.subject
water splitting
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dc.title
On the electrochemistry of YSZ/Ni and related model electrodes
en
dc.type
Thesis
en
dc.type
Hochschulschrift
de
dc.rights.license
In Copyright
en
dc.rights.license
Urheberrechtsschutz
de
dc.identifier.doi
10.34726/hss.2018.33035
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dc.contributor.affiliation
TU Wien, Österreich
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dc.rights.holder
Michael Doppler
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dc.publisher.place
Wien
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tuw.version
vor
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tuw.thesisinformation
Technische Universität Wien
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dc.contributor.assistant
Opitz, Alexander Karl
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tuw.publication.orgunit
E164 - Institut für Chemische Technologien und Analytik