Initial adsorption stage of irreversibly adsorbing Sb on Au(1 1 1)

The adsorption process of irreversibly adsorbed Sb on Au(1 1 1) at open circuit potential (∼0.2 V) was investigated with in situ STM. The adlayer of oxygenated Sb nucleated and grew on terraces and at step edges. The oxygenated Sb domains on terraces were round-shaped islands, whose size ranged from 3 to 6 nm in diameter. The adlayers originating from step edges, on the other hand, grew perpendicularly to the steps to show terrace-like uniform domains. There was no island of Sb on such terrace-like oxygenated domains. In the long term, the island-shaped domains and the terrace-shaped domains were inter-connected to produce a networked monolayer of oxygenated Sb. The network adlayer of oxygenated Sb was modified to a simple layer of nano-islands of elemental Sb, when the electrode potential was held at −0.25 V. Upon a subsequent re-oxidation, the Sb-covered Au(1 1 1) surface showed a complex morphology, filled with many pits and relatively wide islands. Also, atomic images of the Sb layers on Au(1 1 1) at various potentials were presented as well.