Mesoporous TiO ₂ nanowires as bi-functional materials for dye-sensitized solar cells

A bimodal structured TiO ₂ nanowire (NW) was synthesized via metal glycolate-mediated method. Each large NW was comprised of a few nanometers-sized anatase particles, which led to a high specific surface area, 50.4 m ² g ^-1. When the bimodal TiO ₂ NWs were coated onto a spherical nanoparticle-based active layer of the photoelectrode for a dye-sensitized solar cell, the reflectance of the photoelectrode increased by 4-times, compared to a bare active layer. The TiO ₂ NWs increased quantum efficiency of the dye-sensitized solar cell, from 400 to 800 nm wavelengths, which was attributed to both the light-scattering and charge generating effects due to the capability of reflecting incident light and adsorbing large amount of dye molecules.