Cluster Size Effects in the Photocatalytic Hydrogen Evolution Reaction

The photocatalytic water reduction reaction on CdS nanorods was studied as function of Pt cluster size. Maximum H-2 production is found for Pt-46. This effect is attributed to the size dependent electronic properties (e.g., LUMO) of the dusters with respect to the band edges of the semiconductor. This observation may be applicable for the study and interpretation of other systems and reactions, e.g. H2O oxidation or CO2 reduction.