Photovoltaic properties of TiO2 loaded with glutathione-protected silver clusters.

Glutathione-protected Ag clusters (Ag15, Ag25 and Ag29) function as photosensitizers when they are adsorbed on TiO2 electrodes. [Co(bpy)3](2+) is the most appropriate electron donor among the cobalt complexes examined. Ag15 clusters yielded the highest internal quantum efficiency of 28% at 460 nm in the presence of [Co(bpy)3](2+) as a donor.