Redox reaction of a single ferrocene derivative observed by electrochemical scanning tunneling microscope

Abstract

The reactivity of redox reactions is greatly affected by the local structure of the electrode surface on a single-atom/single-molecular scale. Although it is strongly required to investigate the redox reactions on a molecular scale, the number of those reports is limited due to the difficulty of performing in situ measurement with high spatial resolution. In this study, redox reaction of a single ferrocene molecule was observed using an electrochemical scanning tunneling microscope (EC-STM), which is a combination of a scanning tunneling microscope (STM) and electrochemistry (EC). Using a tripod-type molecule as a base, we could stably deposit ferrocenes on the Au (111) electrode both in an isolated and dispersed state, which enables us to observe clear changes in the EC-STM images upon the redox reaction.