Dye-Sensitized Solar Cells with Anatase TiO2 Nanorods Prepared by Hydrothermal Method

The hydrothermal method provides an effective reaction environment for the synthesis of nanocrystalline materials with high purity and well-controlled crystallinity. In this work, we started with various sizes of commercial TiO 2 powders and used the hydrothermal method to prepare TiO 2 thin films. We found that the synthesized TiO 2 nanorods were thin and long when smaller TiO 2 particleswere used, while larger TiO 2 particles produced thicker and shorter nanorods.We also found that TiO 2 films prepared by TiO 2 nanorods exhibited larger surface roughness than those prepared by the commercial TiO 2 particles. It was found that a pure anatase phase of TiO 2 nanorods can be obtained from the hydrothermal method. The dye-sensitized solar cells fabricated with TiO 2 nanorods exhibited a higher solar efficiency than those fabricated with commercial TiO 2 nanoparticles directly. Further, triple-layer structures of TiO 2 thin films with different particle sizes were investigated to improve the solar efficiency.