过渡金属氧化物纳米材料空位形成和迁移机制的透射电子显微学研究

低维过渡金属氧化物独特的物理、化学性能与点缺陷，尤其是氧空位息息相关。然而，结构和性质上的复杂性使得相关的应用研究非常迟缓。本课题拟利用球差校正透射电子显微技术，对过渡金属氧化物纳米材料的原子尺度晶体结构，特别是位错、晶界处的原子构型、成分、价态，及其在温度场以及应力场作用下的演变进行表征。同时，利用第一性原理计算或者（以及）分子动力学模拟作为辅助，深入研究与探讨空位形成、迁移机制以及结构物性关系。课题研究结果将为过渡金属氧化物构效关系的认识提供强有力的补充，并为其合理设计与使用提供借鉴。

The unique physical and chemical properties of low-dimensional transition metal oxides are intimately connected with the point defects, especially the oxygen vacancy. However, a major concern is that the complex structure-property relationships have not been fully understood, stunting new developments. In this context, using the Cs aberration-corrected transmission electron microscopy assisted by the first-principles calculation or (and) molecular dynamics simulation, this project aims to provide a deep understanding of the formation and migration mechanisms of the vacancy and the structure-property relationship in transition metal oxide nanomaterials. Through the detailed static characterization and dynamic evolution of the atomic structures, element distribution, and valence states of the dislocations and grain boundaries, our results may provide fundamentally new insight into the vacancy-mediated physical properties in transition metal oxides, and thus provide guidance for the future applications with improved device design and modelling.