Grain-Boundary Conduction in Gadolinia-Doped Ceria: The Effect of SrO Addition

This study examined the effect of adding SrO on the grain-boundary conduction of (gadolinia-doped ceria) containing . The apparent grain-boundary resistivity at decreased drastically from upon doping with SrO, while the grain-interior resistivity increased gradually from as the SrO concentration was increased up to . Therefore, doping with SrO resulted in the minimum total resistivity. The electron probe X-ray microanalysis and the analysis of the lattice parameters suggest that the 140–500-fold enhancement in the grain-boundary conduction is attributed to the scavenging of the highly resistive siliceous phase by the SrO-containing phase.