Preparation and Electrical Properties of Interconnect Material Made by Substituting Mixed Rare Earth Oxides (Sm2O3, Gd2O3, Eu2O3 and CeO2) for La2O3 in La
La1-xCaxCrO3 (0.1≤ x ≤ 0.4) is usually used as interconnect material for solid oxide fuel cells (SOFCs). In this paper, composite material, the two-phase mixtures of face-centered cubic fluorite structure CayCe1-yO2-y (0 ≤ y≤ 0.2) and orthorhombic perovskite structure [Sm(Eu,Gd)]1-zCazCrO3 (0 < z < 0.3), was prepared by an auto-ignition process in which mixed rare earth oxides (Sm2O3, Gd2O3, Eu2O3 and CeO2) are substituted for La2O3 in La1-xCaxCrO3. The direct current (DC) four-probe technique measurement indicated that the electrical conductivities of specimens increased along with the increase of Ca2+ content (x), especially when x=0.3 and 0.4. The material (x=0.4, about 94% relative density) showed excellent electrical conductivities of 48 Scm-1 in air and 13 Scm-1 in H2 (purity 99.999%) at 700°C respectively, which is about 3 times as high as that of La0.7Ca0.3CrO3.
Wei Pan and Jianghong Gong
H. H. Zhong et al., "Preparation and Electrical Properties of Interconnect Material Made by Substituting Mixed Rare Earth Oxides (Sm2O3, Gd2O3, Eu2O3 and CeO2) for La2O3 in La", Key Engineering Materials, Vols. 336-338, pp. 448-451, 2007