Monatomic steps with a height of 0.25 nm on ultraflat Au(111) surfaces during electrochemical dissolution can be seen for the first time by a laser confocal microscope combined with a differential interference contrast microscope (LCM-DIM). Atomic force microscopy images were acquired in the same area in order to confirm that the step lines observed by LCM-DIM are mostly monatomic steps with the height of 0.25 nm. Successively recorded LCM-DIM images indicated that the anodic dissolution of Au(111) takes place only at step edges in solutions containing chloride anions at potentials near the onset of anodic current.
World Premier International Research Center, Advanced Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aobaku, Sendai 980-8577, Japan.
