CHEMICAL COMPATIBILITY OF RE1-XSRXMNO3+ -DELTA (RE = LA, PR, ND, GD, LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.5) WITH YTTRIA-STABILIZED ZIRCONIA SOLID-ELECTROLYTE/

The chemical reactivity of RE1-xSrxMnO3+/-delta (RE = La, Pr, Nd, Gd) perovskite oxides with yttria stabilized zirconia (YSZ) was investigat ed. Equimolar perovskite/YSZ powder mixtures were prepared and anneale d in air at 1300 degrees C for 120 h. The X-ray diffraction analysis s howed the formation of RE2Zr2O7 and SrZrO3 reaction products for perov skites with low and high Sr-content, respectively. Small amounts of Mn 3O4 were identified for samples that showed high reactivity with YSZ. The extent of RE2Zr2O7 formation is reduced as the ionic radius of the rare earth cation decreases, the only exception being La2Zr2O7, which is formed in minor amounts. The formation of SrZrO3 is favored with i ncreasing Sr-content and decreasing tolerance factor of the perovskite . Among the compositions studied, La1-xSrxMnO3+/-delta showed the best chemical compatibility with YSZ electrolyte. (C) 1998 Elsevier Scienc e Limited. All rights reserved.