Abstract:
Interaction of CO with Cu-Pd and Cu-Ni bimetallic clusters deposited on a ZnO substrate has been investigated by core-level spectroscopy. The surface reactivity of both these alloy clusters increases with the decrease in cluster size, giving rise to dissociative adsorption at small cluster size. The surface reactivity also increases with the increase in Pd or Ni content and the reactivity of the alloy clusters is unlike that of either component metal. Thus, dissociative adsorption occurs on small Cu-Pd clusters unlike on either Cu or Pd clusters of comparable size. The reactivity of the Cu-Ni clusters, on the other hand, falls somewhere between those of Cu and Ni clusters.