In-situ imaging of the electrode surface during electrochemical reactions with a beetle-type electrochemical scanning tunneling microscope

Abstract

In this paper, we present the design and performances of a beetle-type electrochemical scanning tunneling microscope (EC-STM) which allows horizontal tip motion at millimeter range (5 mm x 5 mm). With its symmetrical scanner design inducing a relatively low thermal drift, the beetle-type EC-STM has the desirable ability to operate in a variety of chemical reactions. Atom-resolved high-resolution STM images of highly oriented pyrolytic graphite (HOPG) and Au(111) surfaces in the liquid phase are presented to confirm the scan performance of the beetle-type EC-STM, which also provides in situ information on the electrode surface during electrochemical reactions, including adsorbed- and desorbed- electrolyte and metal electrodeposition. These systemically obtained STM images on the electrode surface clearly demonstrate the high stability of the newly developed ECSTM under reaction conditions.