Branched TiO₂ Nanorods Covered with TiO₂ Nanosheets for Harvesting Solar Energies in Dye-Sensitized Solar Cells

A hierarchical structure of branched TiO2 nanorods covered with TiO2 nanosheets was designed and constructed for harvesting solar energies in dye-sensitized solar cells. Vertical aligned TiO2 nanorod arrays were synthesized on fluorine-doped SnO2 (FTO) by using the electrochemically deposited ZnO nanorod arrays as a template and liquid phase deposition (LPD) method. The resultant TiO2 nanorod was used as a seed and the rutile TiO2 nanorods were firstly synthesized on the surface of anatase TiO2 nanorod by using hydrothermal method. In photocurrent-voltage measurements, 3.56% efficiency was achieved for 1.5um thick nanosheets coated TiO2 nanobranch (NB), which is about 239% higher than the original TiO2 nanorod arrays.