Stability and Efficiency Improvement Based on Low Temperature Processable Electron Transporting Layer in Perovskite Solar Cells

• Main Authors: Huang, Yi-You, 黃翊祐
• Other Authors: 許千樹
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/76919793496040456626

碩士 === 國立交通大學 === 應用化學系分子科學碩博士班 === 104 === In this research we focused on using the low-temperatured electron transporting layer to realize high stability and high efficiency in perovskite solar cells. In the first part of this study, a novel method was adopted to recharge and rejuvenate the perovskite solar cells by immersing the device into methyl ammonium iodide (MAI) solution and heated at 70 °C for 40 sec. We demonstrated Au electrode as a robust one than Al and Ag electrode for ZnO Planar structures rather than ZnO and TiO2 nanoparticles (NPs). In addition to this, degradation path of device was discussed. The scanning electron microscopy images and X-ray diffraction spectroscopy evidenced that the perovskite crystals have been regenerated after degradation (60 days) with the help of MAI as a rejuvenation agent. After long-term aging test with rejuvenation in 185 days, its PCE value was still around 11 % as compared to the original one of 11.6 %. In the second part of this study, we used the promising low temperature titanium dioxide as an electron transporting layer which was doped with gold nanoparticles to improve the electron mobility, short current and compensating the lack of electron in titanium dioxide deep defects. The SCLC measurement showed that the electron mobility increased one order of magnitude for titanium dioxide doped the gold nanoparticles. Futhermore, C-PCBSD was adopted as an organic cathode buffer layer (scaffold) to increase the lead contents in the active layer which was proved in the XPS measurement. The result demenstrated that the C-PCBSD scaffold had the potential to load more perovskite. Two steps deposition method generally had PbI2 residue which may lead to the increase of Pb signal in XPS measurement. In this study, we used a cosolvent of DMSO and DMF (Dimethylformamide) in the second step so as to ensure the complete conversion of perovskite. Combing the advantage of Au nanoparticles in TiO2, C-PCBSD scaffold and cosolvent. We were able to fabricate a high efficiency perovskite solar cell with PCE value of 17.2 %.