TiO2表面光催化动力学的实验研究

项目名称： TiO2表面光催化动力学的实验研究

项目编号： No.21203189

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理化学

项目作者： 周传耀

作者单位： 中国科学院大连化学物理研究所

项目金额： 27万元

中文摘要： 二氧化钛(TiO2)的光催化性质给能源危机和环境污染的解决带来了希望，但是其光催化的微观机理研究还非常缺乏。甲醇在模拟有机污染物的降解和提高TiO2光催化产氢效率方面都有重要应用。目前甲醇在TiO2(110)表面光催化解离的活性位、产物以及动力学过程(Kinetics)都已经有了深入细致的研究，但是其光催化解离的动力(Driving Force)因素依然不清楚。本项目拟利用自行研制的飞秒双光子光电子能谱仪研究TiO2(110)界面激发电子态的一般规律，并结合高灵敏度原位质谱探测技术测量激发光(带隙激发)波长和甲醇的振动对其在TiO2(110)表面光催化解离的影响，探索甲醇在TiO2表面光催化解离的动力。通过对甲醇在TiO2表面光催化解离动力学(Dynamics)的研究，结合密度泛函理论计算，澄清该过程的微观机理，从而更深刻地理解TiO2光催化的本质。

中文关键词： 二氧化钛；光催化；激发态；表面反应；基元过程

英文摘要： The photocatalytic properties of TiO2 provide us some hope to overcome the energy crisis and environmental pollution, however,the fundamental studies of the mechanism of photocatalysis are still lacking. Methanol has been widely applied to model the photooxidation of organic pollutants and promote the hydrogen production over TiO2. Obviously the photochemical properties of methanol on TiO2 play a crucial role in these important processes. So far, the active sites, final products and kinetics of photocatalyzed dissociation of methanol on TiO2(110) have been investigated in detail. However, the driving force for methanol dissociation remains unclear. In this proposal, we plan to study the nature of the excited state on TiO2(110) interface using femtosecond two-photon photoemission spectroscopy (2PPE), and the effect of excitation wavelength (band gap excitation) and the vibrational excitation of methanol on the photocatalyzed dissociation of methanol on TiO2(110) with the combination of 2PPE and highly sensitive in-situ mass spectroscopy (MS). We intend to reveal the driving force for this photocatalytic reaction and to clarify the microscopic mechanism of photocatalyzed splitting of methanol on TiO2 by careful study of the dynamics of this system using 2PPE and MS in combination with density functional theory (DF

英文关键词： TiO2；Photocatalysis；Excited States；Surface Reactions；Fundamental Process