Song Zhongxin, Li Junjie, Davis Kieran Doyle, Li Xifei, Zhang Jiujun, Zhang Lei, Sun Xueliang
College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China.
Department of Mechanical and Materials Engineering, The University of Western Ontario, London, ON N6A 5B9, Canada.
Small Methods. 2022 Nov;6(11):e2201078. doi: 10.1002/smtd.202201078. Epub 2022 Oct 7.
Single atom catalysts (SACs) can achieve a maximum atom utilization efficiency of 100%, which provides significantly increased active sites compared with traditional catalysts during catalytic reactions. Synchrotron radiation technology is an important characterization method for identifying single-atom catalysts. Several types of internal information, such as the coordination number, bond length and electronic structure of metals, can all be analyzed. This review will focus on the introduction of synchrotron radiation techniques and their applications in SACs. First, the fundamentals of synchrotron radiation and the corresponding techniques applied in characterization of SACs will be briefly introduced, such as X-ray absorption near edge spectroscopy and extended X-ray absorption fine structure spectroscopy and in situ techniques. The detailed information obtained from synchrotron radiation X-ray characterization is described through four routes: 1) the local environment of a specific atom; 2) the oxidation state of SACs; 3) electronic structures at different orbitals; and 4) the in situ structure modification during catalytic reaction. In addition, a systematic summary of synchrotron radiation X-ray characterization on different types of SACs (noble metals and transition metals) will be discussed.
单原子催化剂（SACs）可实现高达100%的最大原子利用效率，与传统催化剂相比，在催化反应过程中其活性位点显著增加。同步辐射技术是鉴定单原子催化剂的重要表征方法。金属的配位数、键长和电子结构等几种类型的内部信息均可进行分析。本综述将重点介绍同步辐射技术及其在单原子催化剂中的应用。首先，将简要介绍同步辐射的基本原理以及应用于单原子催化剂表征的相应技术，如X射线吸收近边光谱和扩展X射线吸收精细结构光谱以及原位技术。通过四条途径描述从同步辐射X射线表征中获得的详细信息：1）特定原子的局部环境；2）单原子催化剂的氧化态；3）不同轨道的电子结构；4）催化反应过程中的原位结构修饰。此外，还将讨论对不同类型单原子催化剂（贵金属和过渡金属）的同步辐射X射线表征的系统总结。
