Supermolecular control of charge transfer in dye-sensitized nanocrystalline TiO2 films: towards a quantitative structure-function relationship.

Solid film versus solution-phase charge-recombination dynamics of exTTF-bridge-C60 dyads.

The charge-recombination dynamics of two exTTF-C 6 0 dyads (exTTF=9,10-bis(l,3-dithiol-2-ylidene)-9,10-dihydroanthracene), observed after photoinduced charge separation, are compared in solution and in the solid state. The dyads differ only in the degree of conjugation of the bridge between the donor (exTTF) and the acceptor (C 6 0 ) moieties. In solution, photoexcitation of the nonconjugated dyad C 6 0 -BN-exTTF (1) (BN=1,1'-binaphthyl) shows slower charge-recombination dynamics compared with the conjugated dyad C 6 0 -TVB-exTTF (2) (TVB = bisthienylvinylenebenzene) (lifetimes of 24 and 0.6 μs, respectively), consistent with the expected stronger electronic coupling in the conjugated dyad.…