氧空位缺陷态金属氧化物半导体纳米结构制备及性能研究

Tailored fabrication of defect-engineered metal oxides with tunable nanostructures has attracted considerable attention owing to their critical impacts on the physicochemical properties which show remarkable enhancement in the promising multifunctional properties. Compared with traditional external impurity incorporation, non-stoichiometric metal oxides which have self-doping via aliovalent metal cations without introducing any impurity elements, are beneficial to the formation of minimal structural defects. In this proposal, we will prepare and characterize a number of metal oxide semiconductor nanostructures with tunable oxygen defects such as TiO2-x, ZnO1-x, SnO2-x, MoO3-x, BaTiO3-x, Bi2WO6O3-x, BiVO4-x via a novel and facile approach.The possible formation mechanisms of these novel self-doped metal oxide nanomaterials are also investigated. Furthermore,we will explore the effects of oxygen vacancies in nanostructures on the band structures, optoelectronic conversion, visible-light photocatalytic activity and novel room-temperature ferromagnetism. The relationship between oxygen vacancy states and photocatalytic performance of obtained nanostructures will be studied. Finally, we summarize a survey of efforts to find basic principles based on experimental results. A series of first-principles calculations are performed to evaluate the effect of the presence of oxygen vacancies on the electronic structure and properties, thus further guiding our experiments. Combination of theoretical prediction with experimental data provides improved synthetic strategies for the preparation of other functional defect-engineered nanomaterials.

发展简单实用易操作的合成路径，合理设计并制备出功能导向的氧空位缺陷态金属氧化物纳米结构，具有重要的科学意义和应用前景。利用化合价不同的金属离子的自掺杂，能在金属氧化物纳米材料的晶格结构中伴随产生相应的氧空位缺陷。以溶液相反应为基础，合理选择合成途径，实现对氧空位缺陷态金属氧化物的组成及纳米结构的可控制备，系统研究金属氧化物体系中氧空位缺陷结构的形成机理、存在形式。有效调控缺陷态金属氧化物纳米晶的形貌、尺寸和组成，获得形貌尺寸均匀、稳定的氧空位金属氧化物纳米材料。研究氧空位缺陷态的结构，氧空位浓度等对光电、催化性能调控以及新颖的室温磁性能。总结氧空位缺陷态金属氧化物纳米结构的形成规律，通过密度泛函理论计算缺陷态密度、能级、自旋极化，探索光、电、磁、催化性能与氧空位缺陷结构之间的关系。通过纳米晶体缺陷工程研究，为功能导向、稳定性好的缺陷态无机纳米结构的宏量制备和应用，提供实验方法和理论依据。

发展简单实用易操作的合成路径，合理设计并制备出功能导向的氧空位缺陷态金属氧化物纳米结构，具有重要的科学意义和应用前景。利用化合价不同的金属离子的自掺杂，能在金属氧化物纳米材料的晶格结构中伴随产生相应的氧空位缺陷。以溶液相反应为基础，合理选择合成途径，实现对氧空位缺陷态金属氧化物的组成及纳米结构的可控制备，系统研究金属氧化物体系中氧空位缺陷结构的形成机理、存在形式。有效调控缺陷态金属氧化物纳米晶的形貌、尺寸和组成，获得形貌尺寸均匀、稳定的氧空位金属氧化物纳米材料。研究氧空位缺陷态的结构，氧空位浓度等对光电、催化性能调控以及新颖的室温磁性能。总结氧空位缺陷态金属氧化物纳米结构的形成规律，通过密度泛函理论计算缺陷态密度、能级、自旋极化，探索光、电、磁、催化性能与氧空位缺陷结构之间的关系。通过纳米晶体缺陷工程研究，为功能导向、稳定性好的缺陷态无机纳米结构的宏量制备和应用，提供实验方法和理论依据。