This study examined the effect of adding SrO on the grain-boundary conduction of Ce0.9 Gd0.1 O1.95 (gadolinia-doped ceria) containing 500 ppm Si O2. The apparent grain-boundary resistivity at 300°C decreased drastically from 746.7 to 0.90-1.97 k cm upon doping with 1 mol % SrO, while the grain-interior resistivity increased gradually from 3.1 to 11.6 k cm as the SrO concentration was increased up to 5 mol %. Therefore, doping with 1 mol % 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.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry