DESIGNING SURFACE ALLOYS WITH SPECIFIC ACTIVE-SITES

This report describes a combined experimental and theoretical approach to the problem of designing surface alloys with specific chemical pro perties. Au-Ni(111) surface alloys were prepared and the distribution of active sites was determined by atomically resolved STM as a functio n of Au coverage. Using density functional theory the difference in ac tivation energy for methane over the various sites was determined. The activity of the surface could be predicted directly by combining this information with the distribution of sites. Subsequent measurements o f the activity proved this method to be quantitative and demonstrated that surface alloys with specific activity can be synthesized.