Polythiophene/titanium dioxide (PT/TiO(2)) composites were prepared via in situ chemical oxidative polymerization, and the obtained composites were characterized by X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy (DRS) and transmission electron microscopy (TEM). Using methyl orange (MeO) as a target pollutant, the adsorption capacities and the photocatalytic activities of the resulting composites were investigated. The results indicate that PT/TiO(2) composites have good adsorption capacities due to the electrostatic attraction between the positively charged composite particles' surfaces and MeO; the incorporation of PT into the composites enhances the photocatalytic degradation activity for MeO under both UV and visible light. (c) 2010 Elsevier Ltd. All rights reserved.