Oxygen diffusion across the grain boundary in bicrystal yttria stabilized zirconia

Electrochemical impedance spectroscopy (EIS) measurements in yttria stabilized zirconia (YSZ) with a single Σ13(510)/[001] grain boundary in a common SOFC electrolyte showed that oxide ion diffusion is blocked when it jumps across the grain boundary at operating temperatures between 300 and 525 °C. The EIS results are supported by secondary ion mass spectrometry (SIMS) measurements combined with oxygen isotope annealing on the bicrystal YSZ. The SIMS results showed that the 18O/16O+18O ratio dropped sharply near the grain boundary regions.