Electrochemical scanning tunneling microscopy: Adlayer structure and reaction at solid/liquid interface

The adlayer structure and reaction at the solid/liquid interface has been intensively investigated due to its importance in many physical chemistry and life processes. The emergence of electrochemical scanning tunneling microscopy (ECSTM) provides a new opportunity to study this subject at the atomic and molecular level in aqueous solution. This feature article summarizes some of the latest progress in ECSTM application for the understanding of the structure and reactions taking place at the solid/liquid interface. The adsorption of atoms and organic molecules is clearly revealed, and the knowledge of the underlying molecule/substrate and intermolecular reactions governing the adlayer formation on the surface is deduced. In addition, the effect of external stimuli, such as electrode potential and UV light, on the adlayer structure is demonstrated. Finally, the prospects of future development in this exciting field are outlined.