Chemistry on monolayer metallic films

The chemical behavior of monolayer coverages of one metal on the surface of another, e.g., Ni/W, Fe/W, Pd/W, Cu/Re, Ni/Mo, etc., has recently been shown to be dramatically different from that seen for either of the metallic components separately. These chemical alterations, which modify the chemisorption and catalytic properties of the overlayers, have, in certain cases, been correlated with changes in the structural and electronic properties of the bimetallic system. Representativ e studies are reviewed and discussed as to their relevance to the special properties observed for certain bimetallic catalysts.