Improved‐Performance Dye‐Sensitized Solar Cells Using Nb‐Doped TiO2 Electrodes: Efficient Electron Injection and Transfer

Well-crystallized Nb-doped anatase TiO 2 nanoparticles are prepared by a novel synthetic route and successfully used as the photoanode of dye-sensitized solar cells (DSSCs). The homogenous distribution of Nb in the TiO 2 lattice is confirmed by scanning transmission electron microscopy (STEM) elemental mapping and line-scanning analyses. After Nb doping, the conductivity ofthe TiO 2 powder increases, and its flat-band potential (V fb ) has a positive shift. The energy-conversion efficiency of a cell based on 5.0 mol% Nb-doped Ti0 2 is significantly better, by about 18.2%, compared to that of a cell based on undoped TiO 2 . The as-prepared Nb-doped TiO 2 material is proven in detail to be a better photoanode material than pure TiO 2 , and this new synthetic approach using a water-soluble precursor provides a simple and versatile way to prepare excellent photoanode materials.

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