Utilising intrinsic self-protecting properties of Ni-alloys in fuel electrodes of solid oxide electrolysis cells
File(s)
Published version
Author(s)
Taubmann, Julian
Kristoffersen, Henrik H
Chatzichristodoulou, Christodoulos
Rossmeisl, Jan
Skinner, Stephen
Type
Journal Article
Abstract
The degradation of the fuel electrode composite of Ni and an oxide ion conducting oxide is a central challenge to solve for competitive long-term performance of a solid oxide electrolysis cell (SOEC) to produce green hydrogen. In this study, enhanced durability is observed using microstructural changes in Ni-alloy/Y2O3 stabilised ZrO2 (YSZ) fuel electrodes as an intrinsic self-protecting mechanism. In particular, Ni–Fe alloys offer benefits through the intrinsic mobility of Fe in the alloy phase amid the application of cathodic potentials. This mobility of Fe forms protective surface layers around the Ni–Fe particles and enhances durability by: (1) preventing the loss of contact and mobility of the metal phase away from the most active reaction zones during Ni migration and (2) protecting the surface against accumulation of trace impurities of Si as a ubiquitous contaminant in H2O atmospheres. The combined approach of electrochemical testing of alloy thin-film fuel electrodes prepared by photolithography, postmortem characterisation by low-energy ion scattering (LEIS), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) with density functional theory (DFT) calculations is used to establish a mechanism for self-protecting electrode properties. In addition, other Ni-alloys (Ni–V, Ni–Mn) are proposed by DFT as promising electrode materials with self-protecting properties.
Date Issued
2026-01-15
Date Acceptance
2025-10-22
Citation
Journal of Power Sources, 2026, 662
ISSN
0378-7753
Publisher
Elsevier
Journal / Book Title
Journal of Power Sources
Volume
662
Copyright Statement
Copyright This paper is embargoed until publication. Once published the author’s accepted manuscript will be made available under a CC-BY License in accordance with Imperial’s Research Publications Open Access policy (www.imperial.ac.uk/oa-policy).
License URL
Identifier
10.11583/DTU.29086796.v1
Publication Status
Published
Article Number
238678
Date Publish Online
2025-11-05