Please use this identifier to cite or link to this item: https://doi.org/10.21256/zhaw-1624
Full metadata record
DC FieldValueLanguage
dc.contributor.authorPecho, Omar M.-
dc.contributor.authorMai, Andreas-
dc.contributor.authorMünch, Beat-
dc.contributor.authorHocker, Thomas-
dc.contributor.authorFlatt, Robert J.-
dc.contributor.authorHolzer, Lorenz-
dc.date.accessioned2017-11-30T14:22:02Z-
dc.date.available2017-11-30T14:22:02Z-
dc.date.issued2015-
dc.identifier.issn1996-1944de_CH
dc.identifier.urihttps://digitalcollection.zhaw.ch/handle/11475/1624-
dc.description.abstract3D microstructure-performance relationships in Ni-YSZ anodes for electrolyte-supported cells are investigated in terms of the correlation between the triple phase boundary (TPB) length and polarization resistance (Rpol). Three different Ni-YSZ anodes of varying microstructure are subjected to eight reduction-oxidation (redox) cycles at 950 °C. In general the TPB lengths correlate with anode performance. However, the quantitative results also show that there is no simplistic relationship between TPB and Rpol. The degradation mechanism strongly depends on the initial microstructure. Finer microstructures exhibit lower degradation rates of TPB and Rpol. In fine microstructures, TPB loss is found to be due to Ni coarsening, while in coarse microstructures reduction of active TPB results mainly from loss of YSZ percolation. The latter is attributed to weak bottlenecks associated with lower sintering activity of the coarse YSZ. The coarse anode suffers from complete loss of YSZ connectivity and associated drop of TPBactive by 93%. Surprisingly, this severe microstructure degradation did not lead to electrochemical failure. Mechanistic scenarios are discussed for different anode microstructures. These scenarios are based on a model for coupled charge transfer and transport, which allows using TPB and effective properties as input. The mechanistic scenarios describe the microstructure influence on current distributions, which explains the observed complex relationship between TPB lengths and anode performances. The observed loss of YSZ percolation in the coarse anode is not detrimental because the electrochemical activity is concentrated in a narrow active layer. The anode performance can be predicted reliably if the volume-averaged properties (TPBactive, effective ionic conductivity) are corrected for the so-called short-range effect, which is particularly important in cases with a narrow active layer.de_CH
dc.language.isoende_CH
dc.publisherMDPIde_CH
dc.relation.ispartofMaterialsde_CH
dc.rightshttp://creativecommons.org/licenses/by/4.0/de_CH
dc.subjectDegradationde_CH
dc.subjectSolid oxide fuel cellsde_CH
dc.subjectMapde_CH
dc.subjectMicrostructurede_CH
dc.subject.ddc540: Chemiede_CH
dc.title3D microstructure effects in Ni-YSZ anodes : influence of TPB lengths on the electrochemical performancede_CH
dc.typeBeitrag in wissenschaftlicher Zeitschriftde_CH
dcterms.typeTextde_CH
zhaw.departementSchool of Engineeringde_CH
zhaw.organisationalunitInstitute of Computational Physics (ICP)de_CH
dc.identifier.doi10.3390/ma8105370de_CH
dc.identifier.doi10.21256/zhaw-1624-
zhaw.funding.euNode_CH
zhaw.issue10de_CH
zhaw.originated.zhawYesde_CH
zhaw.pages.end7144de_CH
zhaw.pages.start7129de_CH
zhaw.publication.statuspublishedVersionde_CH
zhaw.volume8de_CH
zhaw.publication.reviewPeer review (Publikation)de_CH
Appears in collections:Publikationen School of Engineering

Files in This Item:
File Description SizeFormat 
2015Pecho-etal_materials-08-05370.pdf5.31 MBAdobe PDFThumbnail
View/Open
Show simple item record
Pecho, O. M., Mai, A., Münch, B., Hocker, T., Flatt, R. J., & Holzer, L. (2015). 3D microstructure effects in Ni-YSZ anodes : influence of TPB lengths on the electrochemical performance. Materials, 8(10), 7129–7144. https://doi.org/10.3390/ma8105370
Pecho, O.M. et al. (2015) ‘3D microstructure effects in Ni-YSZ anodes : influence of TPB lengths on the electrochemical performance’, Materials, 8(10), pp. 7129–7144. Available at: https://doi.org/10.3390/ma8105370.
O. M. Pecho, A. Mai, B. Münch, T. Hocker, R. J. Flatt, and L. Holzer, “3D microstructure effects in Ni-YSZ anodes : influence of TPB lengths on the electrochemical performance,” Materials, vol. 8, no. 10, pp. 7129–7144, 2015, doi: 10.3390/ma8105370.
PECHO, Omar M., Andreas MAI, Beat MÜNCH, Thomas HOCKER, Robert J. FLATT und Lorenz HOLZER, 2015. 3D microstructure effects in Ni-YSZ anodes : influence of TPB lengths on the electrochemical performance. Materials. 2015. Bd. 8, Nr. 10, S. 7129–7144. DOI 10.3390/ma8105370
Pecho, Omar M., Andreas Mai, Beat Münch, Thomas Hocker, Robert J. Flatt, and Lorenz Holzer. 2015. “3D Microstructure Effects in Ni-YSZ Anodes : Influence of TPB Lengths on the Electrochemical Performance.” Materials 8 (10): 7129–44. https://doi.org/10.3390/ma8105370.
Pecho, Omar M., et al. “3D Microstructure Effects in Ni-YSZ Anodes : Influence of TPB Lengths on the Electrochemical Performance.” Materials, vol. 8, no. 10, 2015, pp. 7129–44, https://doi.org/10.3390/ma8105370.


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.