This work reports on the photoelectrochemical properties of an interface comprised by poly(terthiophene) films electrochemically synthesized onto indium-tin oxide substrates and modified with 1-(3-methoxycarbonyl)-propyl-l-phenyl-(6,6)C-61- Important photoelectrical parameters, such as flat band potential, density of charge carriers and depletion layer width were determined for the pristine and hybrid filins. The cathodic photocurrent reflected the p-type semiconducting behavior of the electrosynthesized poly(terthiophene)s. Addition of the acceptor molecule improves the photocurrent at zero bias (similar to 6 mu A cm(-2) at 100 mW cm(-2)) indicating the fullerene derivative acts as an exciton dissociation center, improving the number of charge carriers transported through the polymer to reach the solid-liquid electrolyte interface. (c) 2006 Elsevier B.V. All rights reserved.