PHOTOELECTROCHEMICAL PROPERTIES OF DYE-SENSITIZED TIO2 FILMS CONTAINING DISPERSED GOLD METAL PARTICLES PREPARED BY SOL-GEL METHOD

Effects of gold nanoparticle incorporation on the photoanodic properti es were studied for fluorescein-, rose bengal- and nile blue A-deposit ed TiO2 film electrodes prepared by the sol-gel method, The incorporat ion of gold particles decreased the dye-induced photoresponse in the v isible region, which was ascribed to the retarded electron transport i n the conduction band due to the Schottky barriers at titania/gold int erfaces. The extent of decrease in photoresponse, however, was the sma llest for the electrode sample with rose bengal, whose optical absorpt ion well overlapped the surface plasma resonance of the gold particles . The dipole-dipole coupling between rose bengal molecules and gold pa rticles was thought to enhance the photochemical. processes, resulting in smaller reduction in the photoresponse.