SCANDIA-STABILIZED ZIRCONIA POWDER FOR SOLID OXIDE FUEL CELLS, METHOD FOR PRODUCING SAME, SCANDIA-STABILIZED ZIRCONIA SINTERED BODY FOR SOLID OXIDE FUEL CELLS, METHOD FOR PRODUCING SAID SCANDIA-STABILIZED ZIRCONIA SINTERED BODY FOR SOLID OXIDE FUEL CELLS, AND SOLID OXIDE FUEL CELL

摘要

Provided are: a highly ion-conductive scandia-stabilized zirconia powder for solid oxide fuel cells, which has a highly stable crystal structure, while having low grain boundary resistivity; a scandia-stabilized zirconia sintered body for solid oxide fuel cells; a method for producing this scandia-stabilized zirconia powder for solid oxide fuel cells; and a method for producing this scandia-stabilized zirconia sintered body for solid oxide fuel cells. A scandia-stabilized zirconia powder for solid oxide fuel cells which contains a compound represented by general formula (1) (ZrO₂)_1-x-a(Sc₂O₃)_x(Al₂O₃)_a. In formula (1), 0.09 ≤ x ≤ 0.11 and 0.002 ≤ a 0.01 are satisfied. The crystal structure of this scandia-stabilized zirconia powder for solid oxide fuel cells is in a rhombohedral phase. The crystal structure of a sintered body of this scandia-stabilized zirconia powder is in a cubic phase. The sintered body of this scandia-stabilized zirconia powder has a grain boundary resistivity of 12 Ω·cm or less at 550°C.