Fu Sheng, Sun Nannan, Le Jiabo, Zhang Wenxiao, Miao Renjie, Zhang Wenjun, Kuang Yongbo, Song Weijie, Fang Junfeng
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
School of Physics and Electronics Science, Engineering Research Center of Nanophotonics & Advanced Instrument, Ministry of Education, East China Normal University, Shanghai 200241, China.
ACS Appl Mater Interfaces. 2022 Jul 13;14(27):30937-30945. doi: 10.1021/acsami.2c07420. Epub 2022 Jun 29.
Air fabrication of CsPbI perovskite photovoltaics has been attractive and fast-moving owing to its compatibility to low-cost and up-scalable fabrication. However, due to the inevitable erosions, undesirable traps are formed in air-fabricated CsPbI crystals and seriously hinder photovoltaic performance with poor reproduction. Here, 3, 5-difluorobenzoic acid hydrazide (FBJ) is incorporated as trap regulation against external erosions in air-fabricated CsPbI. Theoretical simulations reveal that FBJ molecules feature stronger absorbance on CsPbI than water, which can regulate trap formations for water erosions. In addition, FBJ with solid bonding interaction to CsPbI can enlarge formation energy of various defects during crystallization and further suppress traps. Moreover, profiling to reductive hydrazine groups, FBJ inhibits traps for oxidation erosions. Consequently, a champion efficiency of 19.27% with an impressive of 1.225 V is realized with the inverted CsPbI devices. Moreover, the optimized devices present superior stability and contain 97.4% after operating at 60 °C for 600 h.
由于与低成本和可扩大规模制造的兼容性，气相制备CsPbI钙钛矿光伏器件一直备受关注且发展迅速。然而，由于不可避免的侵蚀，在气相制备的CsPbI晶体中会形成不良陷阱，严重阻碍光伏性能且再现性差。在此，引入3,5 - 二氟苯甲酰肼（FBJ）来调控气相制备CsPbI过程中的外部侵蚀陷阱。理论模拟表明，FBJ分子对CsPbI的吸附比水更强，可调控水侵蚀导致的陷阱形成。此外，与CsPbI具有牢固键合相互作用的FBJ能在结晶过程中增大各种缺陷的形成能，进一步抑制陷阱。而且，FBJ对还原肼基团进行剖析，可抑制氧化侵蚀导致的陷阱。因此，倒置CsPbI器件实现了19.27%的冠军效率以及令人印象深刻的1.225 V开路电压。此外，优化后的器件具有卓越的稳定性，在60℃下运行600小时后仍保留97.4%的性能。
