In Situ STM Observation of Stable Dislocation Networks during the Initial Stages of the Lifting of the Reconstruction on Au(111) Electrodes

In a surface charge density range between -5 and 28 μC cm-2 , and independent of the support electrolyte, the surface of a Au(111) electrode shows a morphology that differs from both the well-known surface reconstruction and the unreconstructed state and is apparently composed only of fcc regions and dislocations wider than those observed on the reconstructed surface and arranged in rotational domains that follow the three main crystallographic axes of the substrate. The size of the dislocations increases with the positive charge up to 28 μC cm-2 . At higher charge densities, the unreconstructed surface, covered by small triangular islands accommodating the 4-5% excess atoms present in the reconstructed surface, is formed. Our results demonstrate that lifting of the reconstruction is induced by the positive charge on the surface and not by specifically adsorbed anions