Journal article
Coupling between creep and redox behavior in nickel - yttria stabilized zirconia observed in-situ by monochromatic neutron imaging
Department of Energy Conversion and Storage, Technical University of Denmark1
Imaging and Structural Analysis, Department of Energy Conversion and Storage, Technical University of Denmark2
Mixed Conductors, Department of Energy Conversion and Storage, Technical University of Denmark3
Xnovo Technology ApS4
Proton conductors, Department of Energy Conversion and Storage, Technical University of Denmark5
Paul Scherrer Institute6
European Spallation Source ERIC7
Ni-YSZ (nickel - yttria stabilized zirconia) is a material widely used for electrodes and supports in solid oxide electrochemical cells. The mechanical and electrochemical performance of these layers, and thus the whole cell, depends on their microstructure. During the initial operation of a cell, NiO is reduced to Ni.
When this process is conducted under external load, like also present in a stack assembly, significant deformations of NiO/Ni-YSZ composite samples are observed. The observed creep is orders of magnitude larger than the one observed after reduction during operation. This phenomenon is referred to as accelerated creep and is expected to have a significant influence on the microstructure development and stress field present in the Ni-YSZ in solid oxide electrochemical cells (SOCs), which is highly important for the durability of the SOC.
In this work we present energy selective neutron imaging studies of the accelerated creep phenomenon in Ni/NiO-YSZ composite during reduction and also during oxidation. This approach allowed us to observe the phase transition and the creep behavior simultaneously in-situ under SOC operation-like conditions.
Language: | English |
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Year: | 2017 |
Pages: | 167-175 |
ISSN: | 18732755 and 03787753 |
Types: | Journal article |
DOI: | 10.1016/j.jpowsour.2016.11.059 |
ORCIDs: | Makowska, Malgorzata Grazyna , Cleemann, Lars Nilausen , Kuhn, Luise Theil , Frandsen, Henrik Lund and De Angelis, Salvatore |