Application Of Cu ₂ S Composite Electrode In Quantum Dot Sensing Solar Cells

The conversion and utilization of solar energy has become the most ideal method to solve energy crisis and environmental problems in today’s society, so it attracted all the scientists’ attention in the globle. Quantum dot sensitized solar cells with safity and reliablity, simple preparation, low cost, high efficiency in theory and easy of design and other advantage, are considered to be extreme research potential and wide prospects for application in the third generation of solar photovoltaic device. The photoelectric conversion efficiency of quantum dot sensitized solar cells has reached more than 6%, but there is still a long distance for large scale production and application. In this paper, a simple method was used to preparate Cu2S composites counter electrodes with different properties, which has good conductivity and excellent catalytic activity, making performance and stability of CdS/CdSe co-sensitized solar cells be significantly improved.The major research work of this paper:(1) To modify and optimize the photoanode of CdS/CdSe co-sensitization solar cells and achive the best preparation conditions. This thesis mainly researches on the cycles of CdS/CdSe deposition affecting the performance of the cells. The result suggested that when the PS quality and P25 ratio is 4% and the CdS/CdSe deposition for 5/7 cycles, obtaining the highest photoelectric conversion efficiency. (2) Different preparation with thermal decomposition method forming GP-Cu2S composite with different proportion counter electrodes respectively. The different composite counter electrodes of the cells were confirmed by the means of SEM, EDS, XPS, photoelectric properties and a series of characterization testing, the experimental results show that GP-Cu2S composites can improve the conductivity and catalytic activity of the counter electrodes, meanwhile, improve the photocurrent and photoelectric conversion of the cells. GP-3Cu2S composites counter electrodes exhibit the best performance, compared to traditional Pt counter electrodes, the photoelectric conversion performance is improved significantly. (3) Preparated Cu2S particle on FTO in nano size prepared ahead with ion exchange method forming FTO@Cu2S composites counter electrodes, which significantly reduced internal resistance and increased the fill factor of the cells. The photoelectric conversion efficiency is lower than the cell with GP-3Cu2S composite counter electrodes prepared for thermal decomposition method, it mainly because there is not enough amount of Cu2S loading on FTO. This preparation methods need to be further improved.