On the Role of Oxygen in Stabilizing Low‐Coordinated Au Atoms

Abstract

Low‐coordinated gold atoms play a decisive role in the catalytic cycle of low‐temperature CO oxidation or the selective oxidation of olefins. A comparative study of argon and oxygen ion‐bombarded Au(111) surfaces (see microstructure images) reveals a threefold role of adsorbed oxygen: structure formation, stabilization of low‐coordinated gold atoms, and transfer during oxidation reactions.

Solid/electrolyte interface phenomena during anodic polarization of Pd0.2M0.8 (M=Fe, Co, Ni) alloys in H2SO4

“…In situ electrochemical scanning tunneling microscopy and calculation of the bonding state will be useful for further clarification of the solid/electrolyte interface phenomena. On the other hand, Biener et al [27] demonstrated that the adsorption of small amount of oxygen, which was induced by ion bombardment, significantly inhibits the surface diffusion of Au adatoms in the nanostructured Au. Similar situation may be responsible for the present passivity in Pd 0.2 Fe 0.8 and Pd 0.2 Ni 0.8 .…”

Dislocation nucleation in bcc Ta single crystals studied by nanoindentation

“…This treatment creates a nanoscale pit and mound surface morphology with a peak-to-valley roughness of only a few atomic layers [41] and therefore allows one to modify the surface roughness with atomic level control.…”

Reactions of small molecules on gold single crystal surfaces

“…Biener et al [26] used ion-bombarded Au(111) surfaces as a model system to study the role of adsorbed oxygen. Their experiments show that adsorbed oxygen stabilizes low-coordination Au sites, and it is also efficiently transferred to CO 2 as previously observed for SO 2 [27].…”

“…Friend's group studied the reaction of sulfur and oxygen with the Au(111) surface [26,41]. They found by STM that the herringbone reconstruction of Au(111) lifts when either S or O is deposited on the surface.…”

“…Biener et al also studied the interaction of SO 2 with oxygen-sputtered Au(111) (θ oxygen ≤ 0.35 ML) by monitoring the oxygen and sulfur coverages as a function of SO 2 exposure (Figure 8) [26]. Two reaction regimes were observed: oxygen depletion followed by sulfur deposition.…”