中低温下高性能氧离子或质子导体的缺少阻碍了固态氧化物燃料电池的商业化。固体氧化物中氧空位或间隙氧是氧离子迁移的先决条件，且氧空位有助于引入质子，氧缺陷调控、缺陷稳定和离子导电机制是固态氧化物燃料电池用离子导体领域的重点和难点问题。孤立四面体阴离子白钨矿作为一种常见结构，可表现出间隙氧、氧空位或质子导电，但氧空位导电或混合氧空位与质子导电很少，氧缺陷稳定对组成的依赖机制不明晰。本项目拟通过离子取代并采用气动悬浮激光加热等多途径制备系列含氧缺陷的AMO4白钨矿组成，测量其氧离子和质子导电性质，利用粉末衍射、扫描透射电镜、固态核磁共振，第一性原理和分子动力学计算等互补手段研究氧缺陷结构及其对电性能的影响机制，阐述氧缺陷对组成的依赖关系，探索具有良好离子导电性的离子导体。本项目有望为中低温固态氧化物燃料电池提供具有潜在应用价值的电解质材料，并为缺陷稳定与离子导电机制研究提供具有普遍借鉴意义的方法。

The lack of oxide ion or proton conductors with high ionic conductivity at intermediate and low temperature ranges hinder the commercialization of solid oxide fuel cells. The existence of oxygen vacancies or interstitial oxygen defects is prerequisite for oxygen migration in solid oxide electrolytes. Moreover, the presence of oxygen vacancies may introduce protons resulting in proton conduction. Therefore, understanding the stabilization of oxygen defects as well as the underlying mechanism of ionic conductors is key for developing more efficient electrolytes for solid oxide fuel cells. The AMO4-scheelite family, a kind of common structure featured with isolated tetrahedral anions, is known as a class of potential electrolyte candidates due to its structural flexibility to transport interstitial oxygens, oxygen vacancies and even protons. However, electrolytes with oxygen vacancies exhibiting oxygen conduction or mixed oxygen-proton conduction are scarcely reported and currently it is undetermined how the mechanism for oxygen defects stabilization relies on the composition in AMO4 based scheelites. This project intends to design and prepare series of oxygen-defect-contained AMO4 based scheelites through various methods including the innovative aerodynamic levitation-laser heating technique. The oxygen defect structures and the ionic conduction mechanism will be studied in detail using multiple complementary methods including impedance spectroscopy, powder diffraction, scanning-transmission electron microscope, and solid state nuclear magnetic resonance techniques as well as first principle calculation and molecular dynamics simulation. It is foreseen that the project will provide electrolytes with potential application in intermediate and low temperature solid oxide fuel cells and describe novel research methods for the study of defect structures and ion conduction mechanism.