A three-dimensional (3D) multicomponent oxide, Bi12TiO20/TiO2 hierarchical heterostructure was successfully synthesized via a one-step and template-free hydrothermal route. X-ray diffraction and X-ray photoelectron spectroscopy measurements confirm that the composition of the as-fabricated sample is Bi12TiO20/TiO2 composite. Scanning and transmission electron microscopy observation reveals that the as-synthesized sample is microsized flower-like hierarchical networks consisted of Bi12TiO20 nanorods decorated with the primary TiO2 nanoparticles. Extension of the light absorption from the ultraviolet region to the visible-light region was confirmed by UV-vis absorption spectra. Due to the structure-property relationships, the 3D Bi12TiO20/TiO2 heterostructure exhibited enhanced visible photocatalytic activity over that of Bi12TiO20 and TiO2 samples in the decomposition of Rhodamine B in water which is a typical model pollutant. The enhanced photocatalytic activity can be attributed to the extended absorption in the visible light region resulting from the 3D Bi12TiO20/TiO2 heterostructures. and the effective separation of photogenerated carriers driven by the photoinduced potential difference generated at the Bi12TiO20/TiO2 junction interface, demonstrating that the Bi12TiO20/TiO2 heterostructure is a promising candidate as a visible light photocatalyst. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.