Optimization of Photoelectrode for Flexible Dye-sensitized Solar Cell and Preliminary Study of Tandem Cell

Based on the preparation of flexible dye-sensitized solar cells (DSC) by cold isostatic pressing method, optimization of the paste and tandem DSC were investigated. The results presented that hydrothermal treatment of P25 paste could improve the stability of the paste and the efficiency of DSC obviously. Proper amount of 200 nm TiO2 particles was added to the P25 paste to enhance light scattering of photoelectrode. The highest conversion efficiency of 3.11% was obtained at the 4:1 ratio of P25 to 200 nm TiO2. Subsequently, N719 and N749 double-layer tandem DSC were studied. The results show that the efficiency of the double-layer tandem DSC is higher than that of N749 totally sensitized DSC but lower than that of N719 totally sensitized DSC. This may be caused by that thicker photoelectrode hampers the electronic transmission and dyes contact impacts the purity of dyes. The thickness of photoelectrode and cell structure need to be optimized.