Chemical Research in Chinese Universities ›› 2022, Vol. 38 ›› Issue (5): 1172-1184.doi: 10.1007/s40242-022-2245-0

• Reviews • Previous Articles     Next Articles

Advanced TEM Characterization for Single-atom Catalysts: from Ex-situ Towards In-situ

WANG Guowei, KE Xiaoxing, SUI Manling   

  1. Beijing Key Laboratory of Microstructure and Properties of Solids, Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, P. R. China
  • Received:2022-07-20 Online:2022-10-01 Published:2022-10-08
  • Contact: KE Xiaoxing, SUI Manling E-mail:kexiaoxing@bjut.edu.cn;mlsui@bjut.edu.cn
  • Supported by:
    This work was supported by the National Natural Science Foundation of China(No.12074017), the Beijing Municipal High Level Innovative Team Building Program, China(No.IDHT20190503) and the National Natural Science Fund for Innovative Research Groups of China(No.51621003).

Abstract: Clean energy innovation has triggered the development of single-atom catalysts(SACs) due to their excellent catalytic activity, high tunability and low cost. The success of SACs for many catalytic reactions has opened a new field, where the fundamentals of catalytic property-structure relationship at atomic level await exploration, and thus raises challenges for structural characterization. Among the characterization techniques for SACs, aberration-corrected transmission electron microscopy(TEM) has become an essential tool for direct visualization of single atoms. In this review, we briefly summarize recent studies on SACs using advanced TEM. We first introduce TEM methods, which are particularly important for SACs characterization, and then discuss the applications of advanced TEM for SAC characterization, where not only atomic dispersion of single atoms can be studied, but also the distribution of elements and the valence state with local coordination can be resolved. We further extend our review towards in-situ TEM, which has increasing importance for the fundamental understanding of catalytic mechanism. Perspectives of TEM for SACs are finally discussed.

Key words: Single-atom catalyst, Transmission electron microscopy (TEM), Scanning transmission electron microscopy(STEM), Electron energy loss spectroscopy(EELS), Energy dispersive X-ray spectroscopy(EDX), In-situ TEM