Converting CO$_2$ to useful compounds through the solar photocatalytic reduction has been one of the most promising strategies for artificial carbon recycling. The highly relevant photocatalytic substrate for CO$_2$ conversion has been the popular TiO$_2$ surfaces. However, the lack of accurate fundamental parameters that determine the CO$_2$ reduction on TiO$_2$ has limited our ability to control these complicated photocatalysis processes. We have systematically studied the reduction of CO2 at specific sites of the rutile TiO$_2$(110)-1x1 surface using scanning tunneling microscopy at 80 K. The dissociation of CO2 molecules is found to be activated by one electron attachment process and its energy threshold, corresponding to the CO$_2^{\dot-}$/CO$_2$ redox potential, is unambiguously determined to be 2.3 eV higher than the onset of the TiO$_2$ conduction band. The dissociation rate as a function of electron injection energy is also provided. Such information can be used as practical guidelines for the design of effective catalysts for CO$_2$ photoreduction.
Evidence of Photocatalytic Dissociation of Water on TiO2 with Atomic Resolution
TiO 2表面的光催化分解水反应是氢能技术中具有重要意义的基础问题之一，并得到了广泛的研究。然而，存在的第一个反应步骤，直接光解水，已被忽视。在这里，我们提供了明确的实验证据表明，吸附在金红石型TiO 2（110）-1 \times 1表面的水分子可以解离紫外线照射下，使用低温扫描隧道显微镜。结果表明，在光催化作用下，Ti（Ti_（5c））五配位上的一个水分子发生解离，在Ti_（5c）上生成一个羟基，在桥氧排上生成另一个羟基。我们的研究结果揭示了光催化水裂解反应链中缺失的一环，这大大有助于详细了解潜在的机制。
Study of low-energy electron-induced dissociation of 1-Propanol
Indian Institute of Science Education and Research Kolkata（印度科学教育研究所加尔各答分校）；J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences（捷克科学院 J. 赫鲁霍夫斯基物理化学研究所）；Center for Atomic, Molecular and Optical Sciences and Technologies, Joint initiative of IIT Tirupati and IISER Tirupati（提鲁帕蒂原子、分子与光学科学与技术中心（提鲁帕蒂理工学院与印度科学教育研究所提鲁帕蒂分校联合倡议））
