A novel F-doped BiOCl photocatalyst was synthesized for the first time by a simple hydrothermal method and only water was used as the solvent. Samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and ultraviolet-visible (UV-vis) absorption spectroscopy. In determination of photo catalytic activity, the samples were used into photodegradation of rhodamine B (RhB) under visible light irradiation. Results show that F-doped BiOCl exhibits stronger photocatalytic activity after doping. The F-doped BiOCl with F/Bi molar ratio of 3:4 shows the highest degradation performance and high stability. The improvement of photocatalytic activity is mainly ascribed to the synergetic effect of fluorination, in which fluorine ions were doped into crystal lattices and adsorbed onto catalyst surfaces. The primary oxidative species in the reaction system is superoxide radical (center dot O-(2) over bar). The possible degradation mechanism was also proposed based on the experimental results. (C) 2016 Elsevier B.V. All rights reserved.