Formation of di-oxygen species on Ag anion clusters

Experiments using vibrationally resolved ultraviolet photoelectron spectroscopy show that oxygen selectively adsorbs on even-numbered Ag anion clusters, whereas the odd-numbered clusters are not chemically active. We provide evidence that O2 molecularly adsorbs on Ag anion clusters consisting of less than 15 atoms. O2 adsorption pattern for Ag anion clusters is quite analogous to that of Au anion clusters. We suggest that for the reactions efficiently catalyzed by Au-nanocatalysts, Ag nanoclusters can be a promising candidate as a building block of catalysts.