Effect Of The Structure Of TiO 2 On The Performance Of CdS Sensitized Solar Cells

The solar power is becoming an ideal choice to tackle the current energy crisis and environmental problems. The solar cell has many advantages such as safe and reliable, non-pollution, widely available and so on. The quantum dot-sensitized solar cells (QDSSCs) are considered to be the third generation solar cells with great application prospects and research value. A simple method were used to modify TiO2photo-anode in this thesis, and the results showed that the conversion efficiency of CdS-QDSSCs had significantly improved. The stability of Cu2S counter electrodes were preliminary studied in this thesis. The major research work included the following three aspects:1. The preparation process of CdS-QDSSCs were optimized, and the optimum technological conditions were obtained. The influence factors of cell performance about film thickness, CdS cycles and the selection of counter electrode were studied in this thesis. The highest conversion efficiency was1.81%, and it was obtained under the following conditions:(ⅰ) the Cu2S counter electrodes were fabricated by brass foil corrosion;(ⅱ) the film thickness were16μm;(ⅲ) the CdS cycles were7times.2. TiO2photo-anodes were modified by different sizes of polystyrene (PS) spheres, and artificial pores in TiO2films were received. The influence of pores on the cell performance were studied in this thesis. The intentionally introduced pores contributed to better coverage and distribution of CdS sensitizer in TiO2photo-anode films, which were characterized by SEM, EDX, Uv-vis and photoelectric performance analyses. The result suggested PS spheres with diameters of80nm give the best performance, compared to the traditional TiO2photo-anode films, power conversion efficiency increased from1.81%to2.50%, which corresponded to a38.1%enhancement.3. The Cu2S was prepared on FTO conductive glass by precursor method. The results showed the cell had better sealing performance and the polysulfide electrolyte was stable. The conversion efficiency was1.54%, it was lower than brass foil corrosion method. This was mainly due to the preparation of Cu2S evenly enough. Preparation methods need to be further improved.