Morphological synthesis of V2O5/TiO2 nanocomposites with unique core-shell spherical nanostructures and solid sphere nanostructures were achieved by solvothermal method and hydrothermal method, respectively. Owing to their intrinsic semiconductive properties and different nanostructures, both of these two nanocomposites were employed as solar energy transducers to photo-oxidation of arsenic (III) in aqueous solution, with the purpose to better understanding the morphological effect in photocatalysis. It clearly demonstrated that V2O5/TiO2 with core-shell spheres morphology exhibited an excellent photocatalytic activity in the oxidation of arsenite (about 92%), remarkably superior to the one with solid sphere nanostructure, because of its larger specific surface area, enhanced visible harvest ability and improved charge separation efficiency. Furthermore, we discovered that superoxide radicals and photo-generated holes are the active species responsible for the oxidation of As(III) in the V2O5/TiO2 photocatalytic system. (C) 2015 Elsevier B.V. All rights reserved.