Nonalloyed α-phase formamidinium lead triiodide solar cells through iodine intercalation

• 成果类型: Article
• 署名作者: Zhang, Yu; Chen, Yanrun; Liu, Guilin; Wu, Yuetong; Guo, Zhenyu; Fan, Rundong; Li, Kailin; Liu, Huifen; Zhao, Yepin; Kodalle, Tim; Chen, Yihua; Zhu, Cheng; Bai, Yang; Chen, Qi; Zhou, Huanping
• 署名单位: Peking University; Jiangnan University; University of California System; University of California Los Angeles; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; Beijing Institute of Technology; Peking University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-9939
• DOI: 10.1126/science.ads8968
• 发表日期: 2025-01-17
• 页码: 284-290
• 关键词: halide perovskites; STABILITY

摘要

Formamidinium lead triiodide (FAPbI(3)) is considered the most promising composition for high-performing single-junction solar cells. However, nonalloyed alpha-FAPbI(3) is metastable with respect to the photoinactive delta-phase. We have developed a kinetic modulation strategy to fabricate high-quality and stable nonalloyed alpha-FAPbI(3) films, assisted by cogenetic volatile iodine intercalation and decalation. The intercalation of iodine facilitated the formation of corner-sharing Pb-I framework building blocks and reduced the kinetic barrier for alpha-FAPbI(3) formation, whereas the iodine decalation improved the final perovskite film quality in terms of composition purity and overall homogeneity. Solar cells based on this nonalloyed alpha-FAPbI(3) (free of other extrinsic composition ions) achieved a power conversion efficiency of >24%. The devices also exhibited excellent durability, retaining 99% of their original power conversion efficiency after operating for more than 1100 hours at 85 degrees +/- 5 degrees C under illumination.