Flowerlike PtCl4/Bi2WO6 composite photocatalyst was successfully synthesized through a simple two-step method involving a template-free hydrothermal process and the following impregnation treatment. The samples were fully characterized by the study of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and UV-Vis absorption spectra. The results indicated that the doping of Pt species did not affect the crystal structure and the morphology of Bi2WO6 photocatalyst, but it had great influences on the photocatalytic activity of Bi2WO6 towards rhodamine-B (RhB) degradation. Besides, the Pt species was found to be present as PtCl4 in the composite samples, and also an optimal Pt species content on the surface of Bi2WO6 photocatalyst was discovered with the highest photocatalytic ability. The improved photocatalytic performance could be ascribed to the enhanced interfacial charge transfer and the inhibited recombination of electron-hole pairs. Meanwhile, a possible mechanism for RhB photocatalytic degradation over PtCl4/Bi2WO6 catalyst was also proposed. (C) 2010 Elsevier B. V. All rights reserved.