Optimized porous rutile TiO2 nanorod arrays for enhancing the efficiency of dye-sensitized solar cellsElectronic supplementary information (ESI) available. See DOI: 10.1039/c3ee24125d

Highly ordered rutile TiO 2 nanorod arrays (NRAs) are promising architectures in dye-sensitized solar cells (DSCs). However, the efficiency of DSCs based on such photoanodes is still relatively low, largely due to the limited internal surface area. Herein, we report that highly oriented rutile TiO 2 NRAs with film thickness up to ∼30 μm was developed by a facile hydrothermal method. More importantly, an optimized porous rutile TiO 2 NRAs with a large internal surface area was fabricated on the FTO (fluorine-doped tin oxide) substrate via a secondary hydrothermal treatment and when applied as the photoanodes in DSCs, a record efficiency of 7.91% was achieved. A facile two-step hydrothermal method is introduced to enhance the internal surface area of one-dimensional rutile TiO 2 nanorod arrays.