New Type of Periodic Long-Range Restructuring of Ordered Metal Surfaces Induced by Lateral Adsorbate Interactions: Iodide on Au(110) Electrodes

Abstract

A new form of long-range surface restructuring of Au(110) is reported, specifically for Au(110) in aqueous iodide electrolyte at high electrode potentials where an ordered iodide adlayer is present. In situ scanning tunneling microscopy reveals the formation of periodic terrace strips paralleling the (110) direction with widths, ca. 25-40 ÅA, that diminish as the surface potential is increased. The (1 × 1) substrate unit cell, however, remains unaffected. The restructuring is postulated to be due to dipole-dipole repulsive interactions destabilizing terrace sites distant from steps, and hence limiting the size of the substrate-adlayer domains.