Operando Investigation of Heterogeneous Photocatalysis by Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy

光催化反应仅使用阳光作为能源，因此在我们目前的经济转型中远离化石燃料是有价值的元素。对于正在进行的过程的现实见解，光催化转化应该理想地在真实的时间进行研究。虽然MAS NMR光谱是研究界面和催化过程的有力工具，但非均相界面的操作研究仍然是一个巨大的挑战。本项目的目标是在魔角旋转下开发光照射固态NMR光谱，用于二氧化钛模型光催化反应的原位和操作性研究。定制的MAS NMR探头将允许用可变波长和强度的光照射透明转子内的样品浆料。这种方法的潜力将首先在小分子醇的光催化氧化上得到证明。将操作技术与先进的NMR技术相结合，将对催化剂表面及其与液体的界面结构、反应机理和失活过程产生新的见解。在本计画的最后部分，我们将进行光触媒还原二氧化碳的核磁共振研究。

Photocatalytic reactions use only sunlight as energy source and are therefore valuable elements in our current economic transition away from fossil fuels. For realistic insights into the ongoing process, photocatalytic transformations should ideally be studied in real time. While MAS NMR spectroscopy is a powerful tool for investigating interfaces and catalytic processes, the operando investigation of heterogeneous photocatalysis is still a great challenge. The goal of this project is the development of light irradiation solid-state NMR spectroscopy under Magic Angle Spinning for the in situ and operando investigation of model photocatalytic reactions over titania. A custom-built MAS NMR probe will allow to irradiate a sample slurry inside a transparent rotor with light of variable wavelengths and intensity. The potential of this methodology will first be demonstrated on the photocatalytic oxidation of small alcohols. Combination of operando techniques with advanced NMR techniques will yield new insights into the structure of the catalyst surface and its interface with the liquid, into reaction mechanisms and deactivation processes. In the last part of the project, we will implement the operando MAS NMR investigation of the photocatalytic reduction of carbon dioxide.