Transient CO adsorption and the catalytic properties of surfaces - art. no. 081404

摘要

We show that in presence of subsurface oxygen, CO oxidation of oxygen precovered Ag(001) modifies the surface in such a way that CO adsorption is stabilized up to crystal temperatures of 160 K. When diffusion is activated new surface oxide phases form, characterized by oxygen both in surface and in subsurface sites and by a high density of slates just below the Fermi level. Subsurface oxygen accumulation might therefore be relevant for the understanding of the origin of the pressure gap observed for ethylene epoxidation and other important catalytic reactions. References: 25