Photoreactivity of nanostructured semiconducting oxides

本研究将探讨氧化半导体在紫外光照射下形成价带空穴和导带电子的基本过程如何依赖于半导体的晶体结构、形貌和纳米结构。如果氧化物半导体要更广泛地用作光催化剂、光伏电池和其他利用其光电子特性的器件，那么提高对这些过程的理解是至关重要的。该项目将利用圣安德鲁斯大学的Zhou和阿伯丁大学的Howe之间的合作，Zhou在使用电子显微镜合成和材料结构表征方面具有特殊的专业知识，Howe在使用EPR和FTIR光谱来跟踪半导体及其表面发生的过程方面具有经验。将合成不同纳米结构形式的TiO2，并通过原位EPR和FTIR光谱的组合来研究它们的光反应性。我们还将研究复合半导体，以TiO2-WO3为例，以了解为什么这种复合半导体在可见光激发下可以表现出更好的性能。该项目将聘用两名博士生，一名在圣安德鲁斯，另一名在阿伯丁，他们将在这个快速发展的材料化学领域学习互补技能。

This research will investigate how the fundamental processes of formation of valence band holes and conduction band electrons when oxide semiconductors are irradiated with UV light depend on the crystal structure, morphology and nanostructure of the semiconductor. Improved understanding of these processes is crucial if oxide semiconductors are to be used more widely as photocatalysts, in photovoltaic cells, and in other devices exploiting their photoelectronic properties. The project will draw upon a collaboration between the group of Zhou, at St Andrews, with particular expertise in synthesis and structural characterisation of materials using electron microscopy, and Howe, at Aberdeen, who has experinece of using EPR and FTIR spectroscopy to follow processes occurring in semiconductors and at their surfaces. Different nanostructured forms of TiO2 will be synthesised, and their photoreactivity investigated by a combination of in-situ EPR and FTIR spectroscopies. We will also examine composite semiconductors, using TiO2-WO3 as a model example, in order to understand why such composite semiconductors may show improved performance under visible light excitation.The project will employ two PhD students, one in St-Andrews and one in Aberdeen, who will learn complementary skills in this rapidly evolving area of materials chemistry.