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CAUSES OF DEGRADATION IN A SOLID OXIDE ELECTROLYSIS STACK
Figure 2: SEM images and EDS maps of the interface between the
interconnect and its bond layer in the oxygen electrode compartment
Interconnect
Bond layer
Figure 3: Expanded view of the interface between the interconnect
and the bond layer in the oxygen electrode compartment
Interconnect
Bond layer
Figure 4 shows a difference in the diffusion behaviour of Cr in the oxygen electrode compartment
of a SOEC and a SOFC. In the SOEC, oxygen evolves from the electrode/electrolyte/pore interface and
flows out (up) toward the flow field. Gaseous chromium species evolving from the metal flow field must
diffuse against the flow of oxygen emanating from the electrolyte, and as a result Cr is concentrated
in the upper regions in the bond layer. The small amount of Cr at the electrolyte interface does not
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