Steps as adatom sources for surface chemistry: oxygen overlayer formation on Ag(110)
Journal
Surface Science
Journal Volume
330
Journal Issue
3
Pages
L679-L685
Date Issued
1995
Author(s)
Abstract
Surface chemical reactions often require a ready supply of substrate atoms to occur. In principle, steps serve as an efficient source of these atoms, provided that detachment rates from the step edges are sufficiently large. In this paper, we characterize atomic detachment rates from steps on clean Ag(110) by examining step fluctuations. We show that these rates are sufficient to supply atoms to form the added-row reconstruction of oxidized Ag(110) when the oxygen partial pressure is low. For high oxygen pressures, however, we find that step detachment rates are slow compared with oxidation rates, and the step source of Ag is supplemented by vacancy-island generation on the terraces. These results are compared to those obtained for the similar O Cu(110) and O Ni(110) systems. © 1995.
Type
journal article