Title data
Kogut, Iurii ; Steiner, Carsten ; Wulfmeier, Hendrik ; Wollbrink, Alexander ; Hagen, Gunter ; Moos, Ralf ; Fritze, Holger:
Comparison of the electrical conductivity of bulk and film Ce1–xZrxO2–δ in oxygen-depleted atmospheres at high temperatures.
In: Journal of Materials Science.
Vol. 56
(2021)
Issue 30
.
- pp. 17191-17204.
ISSN 1573-4803
DOI: https://doi.org/10.1007/s10853-021-06348-5
Project information
Project title: |
Project's official title Project's id ln-situ-Verfahren zur Bestimmung hoher Sauerstoffdefizite in Cer-Zirkon-Mischoxiden für den Einsatz in der Abgasnachbehandlung MO 1060/29-1 |
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Project financing: |
Deutsche Forschungsgemeinschaft |
Abstract in another language
Featuring high levels of achievable oxygen non-stoichiometry δ, Ce1−xZrxO2−δ solid solutions (CZO) are crucial for application as oxygen storage materials in, for example, automotive three-way catalytic converters (TWC). The use of CZO in form of films combined with simple manufacturing methods is beneficial in view of device miniaturization and reducing of TWC manufacturing costs. In this study, a comparative microstructural and electrochemical characterization of film and conventional bulk CZO is performed using X-ray diffractometry, scanning electron microscopy, and impedance spectroscopy. The films were composed of grains with dimensions of 100 nm or less, and the bulk samples had about 1 µm large grains. The electrical behavior of nanostructured films and coarse-grained bulk CZO (x > 0) was qualitatively similar at high temperatures and under reducing atmospheres. This is explained by dominating effect of Zr addition, which masks microstructural effects on electrical conductivity, enhances the reducibility, and favors strongly electronic conductivity of CZO at temperatures even 200 K lower than those for pure ceria. The nanostructured CeO2 films had much higher electrical conductivity with different trends in dependence on temperature and reducing atmospheres than their bulk counterparts. For the latter, the conductivity was dominantly electronic, and microstructural effects were significant at T < 700 °C. Nanostructural peculiarities of CeO2 films are assumed to induce their more pronounced ionic conduction at medium oxygen partial pressures and relatively low temperatures. The defect interactions in bulk and film CZO under reducing conditions are discussed in the framework of conventional defect models for ceria.
Further data
Item Type: | Article in a journal |
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Refereed: | Yes |
Institutions of the University: | Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Chair Functional Materials > Chair Functional Materials - Univ.-Prof. Dr.-Ing. Ralf Moos Profile Fields > Advanced Fields > Advanced Materials Research Institutions > Research Centres > Bayreuth Center for Material Science and Engineering - BayMAT Research Institutions > Research Units > BERC - Bayreuth Engine Research Center Faculties Faculties > Faculty of Engineering Science > Chair Functional Materials Profile Fields Profile Fields > Advanced Fields Research Institutions Research Institutions > Research Centres Research Institutions > Research Units |
Result of work at the UBT: | Yes |
DDC Subjects: | 600 Technology, medicine, applied sciences > 620 Engineering |
Date Deposited: | 22 Sep 2021 10:08 |
Last Modified: | 22 Sep 2021 10:08 |
URI: | https://eref.uni-bayreuth.de/id/eprint/67080 |