(ZrO2)0.86(Sm2O3)0.14纳米粉体的水热法合成及其烧结体的电性能

以湿化学法制得Zr(OH)₄和Sm(OH)₃的共沉淀为前驱体, 在碱性介质中用水热法合成了(ZrO₂)_0.86(Sm₂O₃)_0.14及(ZrO₂)_0.88(Sm₂O₃)_0.12纳米粉体. 将纳米粉体在较低温度(1450 ℃)下烧结制得了致密的固体电解质陶瓷样品, 比通常高温固相反应法采用的烧结温度(＞1600 ℃)降低了150 ℃以上. XRD测定结果表明, (ZrO₂)_0.86(Sm₂O₃)_0.14纳米粉体及其烧结体均为立方相, 但(ZrO₂)_0.88(Sm₂O₃)_0.12纳米粉体为立方相, 它的烧结体为立方相和单斜相的混合相. 用交流阻抗谱法、氧浓差电池法及氧泵(氧的电化学透过)法研究了(ZrO₂)_0.86(Sm₂O₃)_0.14陶瓷样品在600～1000 ℃下的离子导电特性. 结果表明, 该陶瓷样品在600～1000 ℃下氧离子迁移数为1, 氧离子电导率的最大值为3.2×10^－2 S?cm^－1, 是一个优良的氧离子导体; 它的氧泵性能明显地优于YSZ.

Hydrothermal Synthesis of (ZrO2)0.86(Sm2O3)0.14 Nano-powders and Electrical Properties of Its Sinter

(ZrO₂)_0.86(Sm₂O₃)_0.14 and (ZrO₂)_0.88(Sm₂O₃)_0.12 nano-powders were hydrothermally prepared in basic media by co-precipitation of Zr(OH)₄ and Sm(OH)₃. Green compacts made with the nano-powders prepared hydrothermally could be sintered to above 98% of theoretical density at 1450 ℃, which was 150 ℃ lower than that (＞1600 ℃) used for traditional high-temperature solid state reaction. The results of XRD indicated that both the nano-powders and sinter of (ZrO₂)_0.86(Sm₂O₃)_0.14 are in a cubic phase, and (ZrO₂)_0.88(Sm₂O₃)_0.12 nano-powder is in a cubic phase, but its sinter is in a mixed phase of cubic phase and monoclinic phase. The oxygen ion conduction properties of (ZrO₂)_0.86(Sm₂O₃)_0.14 ceramic were investigated by means of complex impedance, oxygen concentration cell and oxygen pump (electrochemical oxygen permeation) at 600～1000 ℃. The maximal conductivity of the ceramic is 3.2×10^－2 S?cm^－1 in O₂ at 1000 ℃. The conduction in the ceramic is purely oxide-ionic with oxygen ion transference number of 1 over the whole temperature range of 600～1000 ℃. This ceramic is obviously superior to YSZ ceramic in oxygen pump performance.