晶面可控的Sillenite结构可见光响应光催化材料的制备及其光催化性能的晶面依赖性研究

Facet-controlled synthesis of the photocatalysts is an efficient strategy to improve their photocatalytic properties. TiO2 photocatalyst can not utilize the visible light efficiently. In this project, a series of visible-light responsive sillenite-type photocatalysts with controlled facets will be synthesized by the hydrothermal methods and adjusting the process parameters, and introducing the surfactants or capping agents. The photocatalytic properties of the photocatalysts will be enhanced by controlling the morphology, crystal particle sizes, exposed facets and facets coexisting. The project will study the mechanisms of controlling the morphology, crystal particle sizes, exposed facets and facets coexisting of the photocatalysts and their effects on the photocatalytic properties of the photocatalysts according to the experiments and theoretical calculation. The effects of the surface atomic structure and surface electronic structure on the formation and migration of photogenerated charge carriers of the photocatalysts will be discussed. The crystal facet dependence of the visible light photocatallytic property of the photocatalysts will be clarified. The photocatalytic degradation of organic pollutants by the photocatalytsts will be investigated by analyzing the effects of the exposed facets and facets coexisting of the photocatalysts on the active radicals in the photocatalytic process. This study will be very valuable to exploit the new-type visible light photocatalysts, and to enhance the photocatalytic property by controlling the morphology and facet exposing of the photocatalysts.

光催化材料的晶面调控，是改善光催化性能的有效手段之一。常见TiO2光催化材料不能有效利用可见光。本项目拟通过水热等合成方法及控制反应条件，结合表活性剂或覆盖剂的引入，制备出系列晶面可控Sillenite结构的可见光响应光催化材料。通过对其形貌、晶粒尺寸、晶面暴露以及晶面特征进行调控，实现其光催化性能的提高。结合实验和理论分析，研究Sillenite结构可见光催化材料形貌及晶面等微结构调控及其对光催化性能影响的规律；阐明其可见光催化性能对晶面的依赖特性。探讨晶面的表面原子结构等特征对光生载流子的产生、分离的影响。研究光催化材料的晶面暴露与组合对其光催化降解有机污染物过程中反应自由基的影响，揭示其光催化降解有机污染物的机理。该研究对于开发新的可见光催化材料，以及如何通过晶面及形貌调控提高光催化材料的光催化活性，具有重要的理论和实践意义。

本项目通过水热等合成方法及控制反应条件，结合表活性剂或覆盖剂的引入，制备出系列晶面可控 Sillenite 结构的可见光响应光催化材料如Bi12GeO20，Bi12MnO20，和 Bi25FeO40。通过对其形貌、晶粒尺寸、晶面暴露以及晶面特征进行调控，实现其光催化性能的提高。与此同时，本项目通过水热法，合成一系列低维纳米结构的铋基光催化剂及异质结光催化剂，用于高效光催化应用。结合实验和第一性原理计算，研究 Sillenite 结构可见光催化材料和铋基光催化剂的形貌及晶面等微结构调控及其对光催化性能影响的规律。该研究对于开发新型可见响应的光催化材料，并通过调控晶面对其光催化应用，具有重要的实践和理论参考价值。