Observing Electrocatalytic Processes via In Situ Electrochemical Scanning Tunneling Microscopy: Latest Advances.

Electrocatalysis is the foundation of many techniques currently used to address environmental and energy problems. Therefore, understanding the electrocatalytic processes is essential to guide the rational design of electrocatalysts. Scanning tunneling microscopy (STM), developed in the 1980s, remains one of the few techniques that allow surface imaging at the atomic level, making it incredibly useful in electrocatalytic research. In this review, we introduced the basic concept and latest applications of the STM technique for in situ studies of electrocatalytic processes, particularly its capability in active site identification, species adsorption/desorption analysis, surface reconstruction imaging, and electrocatalyst dissolution detection, as well as its advantages and limitations.