Ni-YSZ/YSZ/LSM-YSZ (La0.8 Sr0.2 Mn O3 -yttria-stabilized zirconia) solid oxide fuel cells (SOFCs) with varying Ni-YSZ active-layer compositions were compared electrochemically and structurally using a focused ion beam scanning electron microscope. Stereological analyses showed that the highest triple-phase boundary (TPB) density was at a Ni:YSZ volume ratio of ∼0.5. Although the electrode polarization resistance was minimized at the same composition as the TPB density maximum, the TPB density variation was too small to explain the observed variation in polarization resistance. This implies that polarization resistance was determined not only by TPB density, but also by other structural factors, such as phase tortuosity and contiguity.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Science(all)
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering