Enhancement of dye-sensitized photocurrents by gold nanoparticles: effects of dye-particle spacing.

Photocurrents of a ruthenium dye-TiO(2) system are enhanced by gold nanoparticles (100 or 40 nm diameter) embedded in TiO(2). As dye-particle spacing decreases to 10 nm, enhancement factor and intensity of localized electric fields at the TiO(2) surface increase. A further decrease in the spacing suppresses the enhancement.