Ionic conductivity and microstructure of solid electrolyte La2Mo2O9 prepared by spark-plasma sintering

Dense La2Mo2O9 ceramic electrolytes were prepared with ultrafine powder by the SPS rapid sintering method. The conductivity of the specimens by SPS was much higher than those sintered by conventional process. Moreover, the unilateral alignment of rod-type grains happened in the specimens sintered by SPS at higher temperatures or for longer holding time. The anisotropy in ionic conductivity was attribute to the directional alignment of rod-type grains. The oxygen ion conductivity parallel to the direction of rod-type grains was higher than that perpendicular to the grains.