Photoreactivity of nanostructured semiconducting oxides

这项研究将研究氧化物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被更广泛地用作光催化剂、光伏电池和其他利用其光电特性的设备，对这些过程的了解是至关重要的。该项目将利用圣安德鲁斯的周小组和阿伯丁的豪小组之间的合作，前者在电子显微镜下的材料合成和结构表征方面拥有特别的专业知识，后者拥有使用EPR和FTIR光谱跟踪半导体及其表面发生的过程的经验。将合成不同纳米结构形式的二氧化钛，并用原位EPR和FTIR光谱相结合的方法研究它们的光反应活性。我们还将以二氧化钛-WO_3为模型例子来研究复合半导体，以了解为什么这种复合半导体在可见光激发下表现出更好的性能。该项目将雇用两名博士生，一名在圣安德鲁斯，一名在阿伯丁，他们将学习这个快速发展的材料化学领域的互补技能。

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.