Hybrid photoelectrode by using vertically aligned rutile TiO2 nanowires inlaid with anatase TiO2 nanoparticles for dye-sensitized solar cells

We report a hybrid photoelectrode fabricated by using single crystalline rutile TiO2 nanowires (NWs) inlaid with anatase TiO2 nanoparticles (NPs) for efficient dye-sensitized solar cells. For this purpose, similar to 4-mu m-thick vertically aligned NWs were synthesized on the FTO glass substrate through a solvothermal treatment. Then, as-prepared NW film was treated with the NP colloidal dispersion to construct the NW-NP film. In particular, the NWs offer a fast pathway for electron transport as well as light scattering effect. On the other hand, the inlaid NPs give an extra amount of space for the dye-uptake. Accordingly, the present NW-NP electrode exhibited 6.2% of the conversion efficiency, which corresponds to similar to 48% improvement over the efficiency of the NP-DSC. We attribute this notable result to the synergetic effects of the enhanced light confinement, charge collection, and dye-loading. (C) 2013 Elsevier B.V. All rights reserved.