Effect of Doping of Alcohol-Soluble Fullerene Derivatives on Electron Extraction of TiO2 at Low Temperature

• Main Authors: Bing-Cheng Wang, 王秉承
• Other Authors: 吳春桂
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/7bzpv5

碩士 === 國立中央大學 === 化學學系 === 107 === Perovskite Solar Cell (PSC) has a power conversion efficiency of up to 24.2% (close to the efficiency of silicon wafer based solar cells). The TiO2 (Lt-TiO2) film prepared by low temperature method used as the electron transporting layer (ETL) in the regular PSC has the advantage of low-cost fabrication and flexible substrate applicable, nevertheless, it also has defect density. Furthermore Lt-TiO2 also has low electron extraction ability, resulting in a serious current hysteresis of the corresponding regular PSC. In this study, the fullerene derivatives (such as C60-RT2, C60-RT6, and C70-RT2) with alcohol solubility were prepared to be an additive for Lt-TiO2 electron transporting material (ETM). The additive all improve the photovoltaic performance of Lt-TiO2 ETL and amongst these three fullerene derivatives, C60-RT6 has the best performance. Comparing to Lt-TiO2 film, C60-RT6:Lt-TiO2 nanocomposite film has better electron extraction ability、higher conductivity、less defects and more hydrophilic no matter the ETL was heated at 100°C or dried at ambient atmosphere for 30 minutes. As a result perovskite (Psk) film deposited on the C60-RT6:Lt-TiO2 nanocomposite film has larger particles and better crystallinity than that deposited on Lt-TiO2 ETL. The power conversion efficiencies of the regular PSC besed on C60-RT6:Lt-TiO2 nanocomposite ETL increases to 17.99% (when the ETL was dried at room temperature) and 17.51% (ETL was heated at 100°C) respectively which are higher than those (14.47% and 15.52%, respectively) of the cells based on pure Lt-TiO2 ETL prepared under the same conditions. At the same time the current hysteresis is smaller and the long-term stability in the glove box is better for the cell based on C60-RT6:Lt-TiO2 nanocomposite ETL compared to those using Lt-TiO2 ETLs.