Characterization of scandia stabilized zirconia prepared by glycine nitrate process and its performance as the electrolyte for IT-SOFC

Zirconia stabilized with 8 mol% scandia (8ScSZ) powder was synthesized using glycine nitrate process (GNP) for use as the electrolyte of an intermediate temperature solid oxide fuel cell (IT-SOFC). The powder was compacted into a disc and sintered at 1600 degrees C for 6 h in air for characterization. 8ScSZ consisted of a mixture of cubic and tetragonal phases after sintering. It showed four times as high electrical conductivity (0.159 S/cm) as 8YSZ (0.039 S/cm) at 800 degrees C. The reactivity of 8ScSZ in contact with La0.6Sr0.4Co0.2Fe0.8O3 turned out to be fairly good. Its linear thermal expansion coefficient was measured to be 11.9 x 10(-6)/degrees C. The performance of a single cell was considerably improved when the 8ScSZ electrolyte was substituted for 8YSZ with other conditions kept unaltered. (c) 2005 Elsevier B.V. All rights reserved.