Electron injection and recombination in Ru(dcbpy)2(NCS)2 sensitized nanostructured ZnO

The dynamics of electron-transfer processes between bis(tetrabutylammonium) cis-bis(thiocyanato)bis(2,2'-bipiridine-4,4'-dicarboxylato)ruthenium(II) (called N719) and nanostructured ZnO films were studied by femtosecond and nanosecond spectroscopy. The incident photon to current conversion efficiency (IPCE) for these dye-sensitized electrodes was 36% in the max. of 530 nm, corresponding to a quantum efficiency of 80%. The highest IPCE values were obtained when the electrodes were prepd. under conditions where formation of dye aggregates in the pores of the nanostructured films is avoided. For such films, the electron injection time was in the subpicosecond regime (