Comparison of Y and La-substituted SrTiO3 as the anode materials for SOFCs

Y0.07Sr0.895TiO3 (YST) and La0.2Sr0.7TiO3 (LST) samples sintered and reduced at different temperatures were prepared. The conductivity and chemical expansion of the samples were tested. It was found that the combination of high conductivity and low chemical expansion therefore represents a conflict of material properties for YST and LST samples. The relationship between chemical expansion and sample cracking is discussed. The conductivity of the samples against redox cycles was also tested. Properties with respect to SOFC requirements were compared between LST and YST samples. Suitable preparation conditions for YST and LST as SOFC anode materials were optimized.