Dye-sensitized solar cells（DSCs） have attracted a great deal of attention due to their low-cost and high power conversion efficiencies. They usually utilize an interconnected nanoparticle layer of TiO2 as the electr...Dye-sensitized solar cells（DSCs） have attracted a great deal of attention due to their low-cost and high power conversion efficiencies. They usually utilize an interconnected nanoparticle layer of TiO2 as the electron transport medium. From the fundamental point of view, faster mobility of electrons in Zn O is expected to contribute to better performance in DSCs than TiO2, though the actual practical situation is quite the opposite. In this research, we addressed this problem by first applying a dense layer of Zn O on FTO followed by a mesoporous layer of interconnected Zn O nanoparticle layer, both were prepared by spray pyrolysis technique. The best cell shows a power conversion efficiency of 5.2% when the mesoporous layer thickness is 14 μm and the concentration of the N719 dye in dye coating solution is 0.3 m M, while a cell without a dense layer shows 4.2% under identical conditions. The surface concentration of dye adsorbed in the cell with a dense layer and that without a dense layer are5.00 × 10^（-7） and 3.34 × 10^（-7） mol/cm^2, respectively. The cell with the dense layer has an electron lifetime of-54.81 ms whereas that without the dense layer is 11.08 ms. As such, the presence of the dense layer improves DSC characteristics of Zn O-based DSCs.展开更多
文摘Dye-sensitized solar cells（DSCs） have attracted a great deal of attention due to their low-cost and high power conversion efficiencies. They usually utilize an interconnected nanoparticle layer of TiO2 as the electron transport medium. From the fundamental point of view, faster mobility of electrons in Zn O is expected to contribute to better performance in DSCs than TiO2, though the actual practical situation is quite the opposite. In this research, we addressed this problem by first applying a dense layer of Zn O on FTO followed by a mesoporous layer of interconnected Zn O nanoparticle layer, both were prepared by spray pyrolysis technique. The best cell shows a power conversion efficiency of 5.2% when the mesoporous layer thickness is 14 μm and the concentration of the N719 dye in dye coating solution is 0.3 m M, while a cell without a dense layer shows 4.2% under identical conditions. The surface concentration of dye adsorbed in the cell with a dense layer and that without a dense layer are5.00 × 10^（-7） and 3.34 × 10^（-7） mol/cm^2, respectively. The cell with the dense layer has an electron lifetime of-54.81 ms whereas that without the dense layer is 11.08 ms. As such, the presence of the dense layer improves DSC characteristics of Zn O-based DSCs.
