The adsorption and diffusion of Ag adatoms on a various surface terminations of alumina was studied using density functional theory. Both the Al- and O-terminated surfaces of α-Al2O3(00▪1), as well as the hydroxylated versions of these surfaces, were examined. The results indicated that Ag bonded weakly to the Al-terminated surface and had a low barrier to diffusion. This suggested that the diffusion of Ag on the Al-terminated surface was very rapid. However, the Ag bonded much more strongly to the O-terminated surface; resulting in higher diffusion barriers. The calculations for Ag on hydroxylated surfaces indicated that the presence of water served to lower the barriers to diffusion for Ag atoms, as compared with the O terminated surface, but decreased diffusion when compared with the Al terminated surface. These results described provided a more detailed understanding of the observed surface wetting of other transition metals on hydroxylated alumina surfaces.

An ab initio Analysis of Adsorption and Diffusion of Silver Atoms on Alumina Surfaces. R.Meyer, Q.Ge, J.Lockemeyer, R.Yeates, M.Lemanski, D.Reinalda, M.Neurock: Surface Science, 2007, 601[1], 134-45