Specifically engineered three-dimensional (3D) and 1D morphologies are expected to play significant roles in the development of next-generation dye-sensitized solar cells.In this study, using a hydrothermal approach without a surfactant or template, we attempted to synthesize a 3D hierarchical rutile titanium dioxide (TiO 2 ) architecture by varying the growth temperature and time. X-ray diffraction patterns of the synthesized TiO 2 correlated well with rutile TiO 2 . Scanning electron microscopy images exhibited different nanostructures, such as nanorods, aggregated nanorods, and 3D TiO 2 microflowers comprised of nanorods at 100 C, 130 C, and 160 C, respectively, after growth for 6 h. A significantly improved efficiency was observed for the TiO 2 microflowers. The TiO 2 microflowers exhibited an efficiency of 1.16%, short-circuit current density of 12.8 mA cm À2 , open-circuit voltage of 0.692 V, and fill factor of 0.67.