The novel BiPO4/BiOCl heterojunction composites were successfully fabricated by a facile one-step hydrothermal method. The XRD, SEM, TEM, UV-vis DRS, transient photocurrent and EIS measurements were employed to characterize the phase structures, morphologies, optical properties, and electron-hole separation effect of the photocatalysts. BiPO4/BiOCl composites exhibited much higher photocatalytic activity for the methyl orange (MO) degradation than single BiOCl and BiPO4 under simulated sunlight irradiation. Moreover, the stability test for the optimum synergetic molar ratio of BiPO4/BiOCl composites indicated that the synthetic p-n heterojunction BiPO4/BiOCl photocatalyst had the gratifying reutilization after five cycles. The results of transient photocurrent measurements and EIS demonstrated that the large enhancement of photocatalytic activity could be mainly ascribed to the surface junction of BiPO4/BiOCl composite which can effectively improve electron-hole separation speed during photocatalytic process. (C) 2015 Elsevier B.V. All rights reserved.