| Affiliation: | 1. Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119 China;2. College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, 610059 China;3. Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119 China Dalian National Laboratory for Clean Energy iChEM, Dalian Institute of Chemical Physics Chinese Academy of Sciences, Dalian, 116023 China |
| Abstract: | To simultaneously stabilize cesium lead triiodide (CsPbI3) precursor solution and passivate the defects in CsPbI3 film is greatly significant for achieving highly stable and efficient CsPbI3 perovskite solar cells (PSCs). Herein, an effective redox 4-fluorobenzothiohydrazide (FBTH) is developed to stabilize the precursor solution and passivate iodine/lead-related defects for high-quality CsPbI3 film. The comprehensive research confirms that 1) a new compound FBTH-I is obtained from an effective redox interaction between FBTH and molecular iodine (I2) in perovskite precursor solution, which can effectively impede the formation of I2 molecule and restrain I− migration in perovskite film by forming N–H···I bond; 2) FBTH-I can also passivate Pb-related defects via forming S···Pb interaction. Consequently, the CsPbI3 PSC based on FBTH-treated precursor solution exhibits a fascinating power conversion efficiency (PCE) of 21.41%, which is one of the highest PCE values among the reported pure CsPbI3 PSCs so far, and an outstanding stability against the harsh conditions, such as thermal annealing and continuous light-illumination. |
