ZnO对8YSZ电解质材料的烧结性与电化学性能的影响

用机械混合方法,在8%(摩尔分数,下同)Y2O3稳定的ZrO2(8%in mole yttria stabilized zirconia,8YSZ)中添加ZnO量分别为0,1%,2%,3%,4%,在不同温度下常压烧结制备了ZnO:8YSZ电解质。研究了烧结温度和ZnO含量对ZnO:8YSZ样品的烧结性、致密度、弯曲强度和电导率的影响。由ZnO:8YSZ电解质作为支撑组装了单电池,对电池的性能进行测试和评价。结果表明:在8YSZ中添加ZnO能改善8YSZ材料的烧结性,1400℃烧结2h的4%ZnO:8YSZ样品的致密度达99.9%,3%ZnO:8YSZ样品的弯曲强度超过200MPa,获得明显提高。4%ZnO:8YSZ样品在800℃下的电导率达1.68×10-2S/cm。在相同工作条件下,ZnO:8YSZ单电池比8YSZ单电池具有更好的工作性能和更高的效率,以3%ZnO:8YSZ单电池性能最好。

EFFECTS OF ZnO ADDITIVE ON SINTERABILITY AND ELECTROCHEMICAL PERFORMANCES OF 8YSZ ELECTROLYTE

ZnO：8YSZ （8% in mole yttria stabilized zirconia） electrolyte samples with different amounts of ZnO at 0,1% （in mole,the same below）,2%,3% and 4% were sintered at different temperatures in air. The effects of sintering temperature and ZnO content on the sinterability,relative density,bending strength and conductivity of the ZnO：8YSZ sample were investigated. The cell perform-ances were measured and evaluated using ZnO：8YSZ electrolyte supported configuration. The results show that the addition of ZnO can improve the sinterability of 8YSZ electrolyte. The relative density of 4% ZnO：8YSZ sample sintered at 1 400 ℃ for 2 h reaches 99.9%. The bending strength of 3%ZnO：8YSZ sample increases obviously compared with traditional YSZ,reaching over 200 MPa. Total conductivity of 4% ZnO：8YSZ sample is 1.68 × 10^-2 S/cm at 800 ℃. The cell of ZnO：8YSZ as electrolyte has better performance and higher efficiency than that of 8YSZ as electrolyte in equal working condition,and the cell performance of 3%ZnO：8YSZ as electrolyte is better.