Photoconductivity of an inorganic/organic composite containing dye-sensitized nanocrystalline titanium dioxide

The photophysical properties of solid films of an inorganic/organic composite composed of dye-sensitized nanocrystalline titanium dioxide (TiO2) particles, a conjugated polymer, and a [60] fullerene derivative have been investigated. Large charge collection efficiencies of up to 10% at a field of only 10 V/μm were observed. The photoaction spectrum of the composite is interpreted in terms of three major contributions: a weak photocurrent due to the absorption of photons by the polymer, photogeneration of charges involving the fullerene, and a broad region below the onset of the polymer absorption which involves photophysical processes in the dye-loaded TiO2 nanoparticles.