Structure and growth in metal epitaxy on low-index Au surfaces—a comparison between solid∣electrolyte and solid∣vacuum interfaces

Abstract

On the basis of results of scanning tunnelling microscopy studies we compare the atomic scale mechanism for metal-on-metal epitaxial growth during electrodeposition, at the electrochemical interface and during molecular beam epitaxy in ultrahigh vacuum. Examples include the nucleation and (sub-)monolayer growth of Cu on Au(111), Ni on Au(100) and Ni on Au(111). The results show significant discrepancies in specific growth steps, which can lead also to rather different film morphologies, but they also reveal surprising agreement in other steps in the overall growth process and also in structural aspects. These findings will be discussed, aiming at a unified description of the growth process in both situations. Characteristic differences between growth in the different environments, such as strongly different effective interactions between metallic adspecies, will be elucidated.