STM imaging on catalytic surfaces: from atomic-scale characterization of active sites to operando visualization of surface reactions

Scanning tunneling microscope (STM) is an ideal technique to get molecular-level insight into the physical and chemical processes occurred at the interface between a solid and a fluid, due to its atomic-scale spatial resolution on crystalline surfaces. STM on the one hand offers atomic level resolution on catalytically active surface sites (e. g. single atom sites, defects, and steps) in a static state, on the other hand allows the monitoring of dynamic processes at interfaces, including molecular adsorption and desorption, structural transition and surface reconstruction processes during chemical reactions on solid surfaces. With the help of complementary techniques, STM has been applied to acquire crucial information on some industrially important reactions for the design and development of new and better catalysts. Here we present a summary of recent progress in STM imaging on catalytic surfaces, covering the advances in the field and a perspective for future studies.