A novel flower-like BiOBr0.9I0.1/BiOI heterostructure was fabricated by a simple one-pot method at room temperature. Under visible light (lambda > 400 nm), the as-prepared BiOBr0.9I0.1/BiOI photocatalysts with different BiOBr0.9I0.1/BiOI contents exhibited a notably enhanced degrading efficiency for methyl orange and phenol solutions, among which 10% BiOBr0.9I0.1/BiOI possessed the highest photocatalytic activity. The activity improvement of BiOBr0.9I0.1/BiOI could be ascribed to the synergetic effects of ion doping and heterostructure. On the basis of the Mott-Schottky analysis, a new 1- ion doping energy level formed on top of the valence band of BiOBr strengthened the visible light absorption. Moreover, the heterojunction interface of BiOBr0.9I0.1/BiOI efficiently reduced the recombination of electron-hole pairs. This study reveals that the coupling of ion doping and heterojunction structure played significant synergetic effects on the highly efficient generation and separation of photo-generated carriers. (C) 2015 Elsevier B.V. All rights reserved.