The work demonstrated the advantages of titanium-alkoxide-dyes in improvement of photocurrent conversion, and revealed the synergistic effects of dye and auxiliary ligand.

Supertetrahedral nano-CuInS clusters are prepared and the crystals can instantly dissolve in a solution having high ionic strength to create a solution with uniform T5 clusters. The nano-CuInS clusters can be easily wet-modified on a TiO2 electrode and show excellent photo-sensitive properties.

A unique titanium oxo cluster with a ferrocene ligand was synthesized and characterized by single crystal X-ray analysis. Six ferrocene carboxylates coordinate to a D TiO core to be a redox active cluster 1, [TiO(OPr)(OCFc)]. An analogue 2, [TiO(OPr)(OCBu)], where the redox active ferrocene group is replaced by isobutyrate, is also reported as a contrast. The six ferrocene moieties in 1 are structurally identical to give a main redox wave at E = 0.62 V in dichloromethane investigated by cyclic voltammetry. Photocurrent responses using electrodes of clusters 1 and 2 were studied, and the response properties of 1 are better than those of 2. The electronic spectra and theoretical calculations indicate that charge transfer occurs from ferrocene to Ti(IV) in 1, and the presence of the ferrocene moiety gives efficient electron excitation and charge separation. Cluster 1 is a cooperative system of TiO cluster and redox active ferrocene. Photocurrent response properties of an electrode of 1 for four saccharides, glucose, fructose, maltose, and sucrose, were tested, and only reducing sugars were responsive. The electrode of 2 is also photocurrent responsive to saccharides, but the current densities are lower than those of redox active 1.