Branched rutile TiO2 nanorod arrays were directly synthesized on the F-doped tin oxide (FTO) substrate through a two-step hydrothermal treatment by a seeding method with TiO2-nanorods as seeds. The samples were characterized respectively by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and field-emission scanning electron microscopy (FESEM). Results showed that TiO2 nanorods with nanobranches (TiO2-NB) grew vertically on the FTO substrate. XRD and HRTEM results confirmed that the TiO2-NB arrays were single-crystalline rutile. The optical properties of the samples were studied with a UV-vis spectrometer. The photocatalytic activity of the TiO2-NB film is better than that of P25 particulate film. Direct electrical pathway and improved light-harvesting efficiency were crucial for the superior photocatalytic activity of the TiO2-NB arrays. (C) 2011 Elsevier B.V. All rights reserved.