Influence of the dropping time of antisolvent on the formation of perovskite thin films and their application in photovoltaic cells

• Main Authors: Sheng-De Wong, 翁勝德
• Other Authors: Sheng-Hui Chen
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/yn9u98

碩士 === 國立中央大學 === 光電科學與工程學系 === 106 === In the recent decade, the power conversion efficiency (PCE) of perovskite solar cells was improved to more than 20%. Perovskite thin films can be fabricated by using thermal evaporation methods or spin coating processes. Spin coating methods were widely applied to the formation of the high-quality perovskite thin films due to the low-cost processes. In this thesis, the device architecture of the perovskite solar cell is silver/ PC61BM/CH3NH3PbI3/PEDOT:PSS/ITO/glass. Silver and ITO are deposited as the cathode and the anode, respectively. PCBM and PEDOT:PSS are deposited as the electron transport layer and the hole transport layer, respectively. The CH3NH3PbI3 perovskite thin film is the light absorbing layer. In order to achieve the high efficient perovskite solar cell, we investigated the effect of the dropping time (DT) of the washing solvent (antisolvent) on the photovoltaic performance of perovskite solar cells. When the DMF/DMSO (9:1 v/v) mixture is used as the solvent of the perovskite precursor and the DT of the antisolvent is 17s, the high-quality perovskite thin film can be achieved with high PCE. In addition, the DT of the antisolvent significantly affects the appearance of the perovskite thin films. Therefore, the X-ray diffractometer, transmission spectrometer, photoluminescence (PL) spectrometer, time-resolved PL detector, optical microscope, atomic-force microscope and water-droplet contact angle imaging system were used to analyze the surface, structural and optoelectronic properties of the perovskite films in order to understand the role of the DT of the antisolvent in the formation of a perovskite thin film. Finally, the highest PCE of the perovskite solar cells is 13.19 %. The corresponding open-circuit voltage (VOC), short-circuit current density (JSC) and fill factor (FF) are 0.997 V, 20.52 mA/cm2 and 64.47%, respectively.