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以电化学方法研究了ＺｒＯ２－Ｔｂ２Ｏ３．５－Ｙ２Ｏ３复合氧化物体系的混合电导和氧渗透性，并从固体缺陷化学的角度进行了讨论．结果表明，在所研究的组成范围内（Ｔｂ含量高达５０ｍｏｌ％），试样皆为面心立方萤石结构，其晶格常数随Ｔｂ含量增多而线性增大．Ｔｂ元素的变价及其随温度和组成的依赖关系决定了体系的混合电导性质．Ｔｂ含量的增多导致电子电导的增大，而Ｙ的掺入对其电性质的改善不明显．氧渗透性决定于材料电子电导和离子电导的综合作用，氧渗透通量较ＺｒＯ２－Ｙ２Ｏ３体系提高了１～２个量级．氧渗透过程机制遵循氧离子和电子空穴通过材料膜的体扩散为控制步骤这一模型．
The mixed conductance and oxygen permeability of ZrO2-Tb2O3.5-Y2O3 composite oxide system were investigated electrochemically and discussed from the viewpoint of solid defect chemistry. The results show that all samples have a face-centered cubic fluorite structure with a Tb content up to 50mol%. The lattice constant increases linearly with increasing Tb content. The change of Tb element and its dependence on temperature and composition determine the mixed conductance of the system. The increase of Tb content leads to the increase of electron conductance, while the incorporation of Y has no obvious improvement on the electrical properties. Oxygen permeability depends on the combined effect of electronic conductivity and ionic conductance of the material. The oxygen permeation flux is 1 to 2 orders of magnitude higher than that of the ZrO2-Y2O3 system. The mechanism of oxygen permeation follows the model of control steps for the diffusion of oxygen ions and electron holes through the bulk of the material film.