Dynamics of the Au (001) surface in electrolytes: In situ coherent x-ray scattering.

We studied the dynamics of the Au (001) surface in 0.1 M HClO4 electrolyte solution using coherent surface x-ray scattering (CSXS). We find that edges of steps and islands on the Au (001) surface are highly dynamic in electrolyte and evolve continuously even at room temperature. The evolving speed increases nearly two orders of magnitude when the quasihexagonal reconstruction is lifted during slow potential sweep and is higher by more than four orders of magnitude than the speed measured previously in vacuum. In addition, we find that surface lattice dynamics appear when the reconstruction is lifted, and they are faster by two orders of magnitudes than the edge dynamics. Complementary scanning tunneling microscopy images are also presented for visual confirmation of the changes measured by the CSXS technique. [ABSTRACT FROM AUTHOR]