Multilayer films of a water-soluble polythiophene derivative and CdSe nanoparticles were prepared by layer-by-layer deposition. Cyclic voltammograms of the multilayers indicated that they have good electrochemical activity and stability. The multilayers exhibit swift and steady photoresponsive properties, indicating that the multilayer structure in the composite films is favorable for charge separation and transportation. The incident photon to collected electron conversion efficiency of the multilayer is over 6%. (c) 2008 Elsevier B.V. All rights reserved.