Anisotropic dissolution of an Au(111) electrode in perchloric acid solution containing chloride anion investigated by in situ STM : The important role of adsorbed chloride anion

摘要: The anodic dissolution process of Au(111) in a 0.1 M perchloric acid (HClO4) solution containing chloride anion (Cl-) was investigated using an situ scanning tunneling microscope. initial gold observed at the step sites when electrode potentials became more positive than +1.0 V. rate increased as potential positive. When +1.35 V, on terraces also observed. anisotropically proceeds layer-by-layer mode. Step lines along [110] direction, which were found double-layer region, disappeared, and ones [211] direction newly formed during process. surface rougher +1.45 where oxide formation simultaneously took place. completely passivated +1.7 mechanism for anisotropic dissolutio...