Zhang Boyao, Hu Zhaosheng, Su Jie, Gong Zhen, Guo Xing, Chen Xiaoqing, Yang Yingguo, Lin Zhenhua, Ding Liming, Hao Yue, Chang Jingjing
State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology, School of Microelectronics, Xidian University, 2 South Taibai Road, Xi'an, 710071, Shaanxi, China.
Advanced Interdisciplinary Research Center for Flexible Electronics, Xidian University, 2 South Taibai Road, Xi'an, 710071, Shaanxi, China.
Angew Chem Int Ed Engl. 2025 Jan 2;64(1):e202413550. doi: 10.1002/anie.202413550. Epub 2024 Oct 29.
Fluoride anion (F) with extremely high electronegativity has been under intensive investigation in perovskite solar cells due to its remarkable defect suppression and great improvement of device performance. Nevertheless, these researches only focus on the surface, grain boundaries, or interface modification, the direct insertion of F into the crystal lattice of regular lead halide perovskite films is still unrevealed. Herein, F was successfully incorporated into the perovskite lattice by overcoming the insolubility of PbF via the introduced pyridinium halide as a novel volatile solubilizing ligand. The strong electronegativity of F can strongly increase the binding energy of all the ions in CsPbIBr and inhibit their defect formations. A trace amount of F incorporation not only enhanced the optoelectronic properties but also effectively mitigated the ion migration and phase separation simultaneously. The photovoltaic performance and operational stability of perovskite solar cells were significantly improved with a champion efficiency of 17.78 % (38.01 %) under AM 1.5G (1000 lux indoor light). Moreover, F can also be directly inserted into the hybrid perovskite lattice and greatly stabilized crystal-phase, enabling efficient fully MA-free FAPbI devices with 25.10 % efficiency. Our strategy sheds light on F-containing perovskites and provides a promising way to tackle ion migration and stabilize the crystal phase in halide perovskites.
由于具有显著的缺陷抑制作用和对器件性能的极大提升，电负性极高的氟阴离子（F）在钙钛矿太阳能电池领域受到了广泛研究。然而，这些研究仅聚焦于表面、晶界或界面修饰，F直接插入常规卤化铅钙钛矿薄膜晶格的情况仍未被揭示。在此，通过引入卤化吡啶鎓作为一种新型挥发性增溶配体，克服了氟化铅的不溶性，成功将F掺入钙钛矿晶格。F的强电负性能够显著提高CsPbIBr中所有离子的结合能，并抑制其缺陷形成。微量的F掺入不仅增强了光电性能，还同时有效减轻了离子迁移和相分离。在AM 1.5G（1000勒克斯室内光）条件下，钙钛矿太阳能电池的光伏性能和运行稳定性得到显著提升，最高效率达到17.78%（38.01%）。此外，F还能直接插入混合钙钛矿晶格并极大地稳定晶相，从而实现效率为25.10%的高效全无甲脒（MA）的FAPbI器件。我们的策略为含F钙钛矿提供了启示，并为解决卤化钙钛矿中的离子迁移和稳定晶相提供了一条有前景的途径。
