基于同步辐射技术的金属氧化物表面结构对于光催化CO2转化性能的调控研究

Photocatalytic conversion of CO2 to fuels will play an important role in the future energy and environmental applications. In literature, it has been reported that the surface structures of metal oxides may impact on their semiconductor energy band structures, photoexcited carrier behavior, and molecular adsorption and activation involved in the photocatalytic process; however, it remains elusive about the detailed working mechanisms and structure-property relationships. In this project, we propose to establish the structure-property relationships between surface structures and photocatalytic performance by precisely controlling and in-situ characterizing the surface structures of metal oxides as well as analyzing their performance in each step of photocatalysis, with a focus on several synchrotron radiation characterization techniques. A combination of controlled synthesis, advanced characterizations and theoretical simulations will be employed to facilitate the research. The focus of research will include: (1) chemical control over the surface facets, defects and dangling bonds of metal oxides and their X-ray absorption fine structure characterizations; (2) steady-state photoemission spectroscopy and X-ray absorption spectroscopy characterizations to resolve energy band structures of metal oxides with surface defects; (3) X-ray absorption spectroscopy analyses to reflect the charge transfer between atoms in metal oxides; (4) X-ray absorption spectroscopy detections and analyses to reveal CO2 and water molecular adsorption/activation behavior on the surface of metal oxides. In combination with the theoretical calculations and other characterization techniques, we will gain deep insight into the intrinsic relationship between the surface structures of metal oxides and their photocatalytic performance.

光催化CO2转化燃料反应在未来的能源环境应用领域中将起很重要的作用。已陆续有文献报道金属氧化物表面结构对其半导体能带结构、光生电荷行为、分子吸附活化等光催化工作过程的影响，然而其作用机制和构效关系尚不明了。在本项目中，我们将基于几种同步辐射表征技术，配合其他合成、表征和理论等研究手段，通过精细调控和原位表征金属氧化物表面结构，探知其在光催化过程中各个步骤行为，从而建立表面结构与光催化性能的构效关系。研究重点主要包括：（1）金属氧化物表面晶面、缺陷及悬键的化学调控和X 射线吸收精细结构表征；（2）具有表面缺陷的金属氧化物能带结构的光电子能谱和X射线吸收谱静态表征；（3）金属氧化物原子间的电荷转移过程的X射线吸收谱分析；（4）金属氧化物表面CO2和水分子吸附活化行为的X射线谱学检测与分析。结合理论计算和其他表征手段，获得金属氧化物表面结构与其光催化性能之间内在联系的信息。

光催化CO2转化燃料反应在未来的能源环境应用领域中将起很重要的作用。已陆续有文献报道金属氧化物表面结构对其半导体能带结构、光生电荷行为、分子吸附活化等光催化工作过程的影响，然而其作用机制和构效关系尚不明了。本项目基于几种同步辐射表征技术，在金属氧化物表面晶面、缺陷及悬键的化学调控和X 射线吸收精细结构表征、具有表面缺陷的金属氧化物能带结构的光电子能谱和X射线吸收谱静态表征、金属氧化物原子间的电荷转移过程的X射线吸收谱分析、金属氧化物表面CO2和水分子吸附活化行为的X射线谱学检测与分析等四个方面开展了系统工作。经过三年的执行，本项目组已经在金属氧化物光催化CO2转化方面取得了突破性进展，并产生了许多未预期的新成果，辐射到其他一些催化领域（如电催化和有机催化反应体系）。通过该系列研究，理清了光催化过程中各个步骤行为，从而建立了表面结构与光催化性能的构效关系。部分结果已在J. Am. Chem. Soc.（4篇）、Angew. Chem. Int. Ed.（3篇）、Adv. Mater.（3篇）、Chem. Soc. Rev.（1篇）等国际重要期刊上发表34篇通讯作者论文，入选科睿唯安全球高被引科学家榜单和爱思唯尔中国高被引学者榜单。已毕业9名博士生和3名硕士生，培养3名博士后，项目负责人获国家杰出青年科学基金资助，入选科技部中青年科技创新领军人才。