Comparison of microstructural evolution of fuel electrodes in solid oxide fuel cells and electrolysis cells

By M. Trini, A. Hauch, S. D. Angelis, Xiaofeng Tong, P. Hendriksen, Ming Chen. Journal of Power Sources, 2020

159 citations recorded by the source corpus.

Abstract Solid oxide cells are electrochemical devices used for the conversion of chemical energy to electrical energy (Solid Oxide Fuel Cells-SOFC) and vice versa (Solid Oxide Electrolysis Cells-SOEC). However, long-term performance degradation impedes the widespread commercialization of the technology. To investigate the effects of operation mode on the degradation of Ni/yttria-stabilized zirconia (YSZ) electrodes, two cells from the same production batch are tested for 1000 h at 800 °C; one as SOFC and the other as SOEC. The cells are fed with the same gas composition at the fuel inlet side (p(H2O)/p(H2) = 0.5/0.5) while the direction of the current (±1 A cm−2) is reversed. It is found that Ni coarsening occurs to a similar extent in both operation modes while Ni depletion is only observed in SOEC mode, in the region close to the electrode/electrolyte interface. Here, the Ni/(Ni + Zr + Y) atomic ratio decreases from ~0.49 before operating the cell to ~ 0.28 and the SOEC shows a pronounced decrease in percolating triple phase boundaries (TPBs). The wettability of Ni on YSZ is studied and hypotheses are presented to correlate the phenomena of Ni coarsening and Ni depletion with the cell operation mode.

Subfields: Biomedical Engineering, Materials Chemistry, Renewable Energy, Sustainability and the Environment

View Paper: https://www.semanticscholar.org/paper/19c728b664972599f1e9c8e42ea82b16b6691f6e

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Biomedical Engineering

1. M. Mogensen
2. A. Hauch
3. R. Küngas
4. S. Ebbesen

In Materials Chemistry

1. A. Hauch
2. M. Mogensen
3. R. Küngas
4. J. Hansen
5. A. Hansen
6. P. Blennow
7. Brian Vad Mathiesen
8. S. Ebbesen

In Renewable Energy, Sustainability and the Environment

1. R. Küngas
2. Brian Vad Mathiesen

Citations in the corpus

• Recent advances in solid oxide cell technology for electrolysis (2020, background): “Note that Ni migration is observed for cells operated in electrolysis mode but is not seen to the same extent in cells tested in fuel cell mode under similar test conditions, thus clearly pointing toward the local pO2 in the fuel electrode as being the critical parameter (53).”