Interaction between silver nanowires and CO on a stepped platinumsurface

摘要

We studied the interplay between Ag decoration of a stepped Pt(355) surface and CO adsorption byin situ high-resolution x-ray photoelectron spectroscopy. Varying amounts of Ag deposited at 300 Kinitially lead to a row-by-row growth starting from the lower Pt step edges. Such decoration of thestep sites results in a change in the CO adsorption behavior. An apparent blocking of step sites forlow CO coverages is attributed to a change in the electronic structure, resulting in a C is bindingenergy of CO at step sites being equal to that for CO at terrace on-top sites in the presence of Ag.Higher CO coverages induce the formation of embedded Ag clusters within the upper terraces, thusfreeing up a part of the original Pt step sites for CO adsorption, as was derived by a comparison todensity functional theory calculations in the corresponding surface models