In-Situ 0bservation of Metal Surfaces in Aqueous Solutions with an Electrochemical STM

Abstract

In-situ observation at high magnification of materials being damaged by aqueous corrosion and corrosion fatigue is significant in the understanding of these mechanisms. In this study, in-situ observation of Au, Fe, SUS304 steel and SNCM439 steel under potential control in 1%NaCl and 0.1%HNO₃ solutions is performed by STM. The STM image can be observed for all materials both in anodic and cathodic potentials if the proper tunnel bias is applied. In cathodic potentials the STM image does not change with time, while in anodic potentials the STM image changes rapidly unless the material is in a passive condition.