Preparation and Properties of Yttrium Doped Barium Zirconate-cerate Proton Conductors

Abstract

Yttrium doped barium zirconate-cerate(BaZr0.90-xCexY0.10O3-δ,x=0.09,0.18,0.27,BZCY) powders were synthesized by the conventional solid state reaction route.The x value was optimized to be 0.27 in the composition range.That is to say,the sample with x=0.27 had the best sinterability and conductivity among the three composites. The sintering behavior and electrical conductivity could be further improved by optimizing the addition content of ZnO sintering aid.ZnO was able to form a solid solution with BZCY,resulting in the enhancement of sinterability. As increasing the amount of ZnO,density of the sintered samples increased.However,conductivity did not increase monotonously with the addition of ZnO.When the content of ZnO was 2mol%(C3-Z2),the sample had the highest DC conductivity,reaching 9.27 mS/cm at 800℃ in wet H2 atmosphere.A small shift of the main peaks of the XRD pattern for the sample C3-Z2 was clearly observed compared with the standard patterns for BaCeO3 and BaZrO3. The XRD pattern of the sample C3-Z2 was in a good agreement with that of BaCe0.4Zr0.6O3 sample.