Sputtered Nb2O5 as an effective blocking layer at conducting glass and TiO2 interfaces in ionic liquid-based dye-sensitized solar cells

The thin Nb2O5 layer works as a remakable blocking layer when deposited by the rf magnetron sputtering method between fluorine-doped tin oxide and a mesoporous TiO2 layer, improving open-circuit photovoltage ( V-oc) and fill factor ( FF) with power conversion efficiency over 5.5% at 1 sun irradiation of the dye-sensitized TiO2 solar cells using ionic liquid electrolytes.