Li Zhigang, Cao Yang, Feng Jiangshan, Lou Junjie, Liu Yucheng, Liu Shengzhong Frank
Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Materials Science and Engineering, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, Institute for Advanced Energy Materials, Shaanxi Normal University, west chang'an street, Xi'an, Shaanxi, 710119, P. R. China.
Institute of Nanoscience and Nanotechnology, School of Materials and Energy, Lanzhou University, Lanzhou, Gansu, 730000, P. R. China.
Small. 2023 Nov;19(45):e2303017. doi: 10.1002/smll.202303017. Epub 2023 Jul 21.
With better light utilization, larger tolerance factor, and higher power conversion efficiency (PCE), the HC(NH ) (FA)-based perovskite is proven superior to the popular CH NH (MA)- and Cs-based halide perovskites in solar cell applications. Unfortunately, limited by intrinsic defects within the FA-based perovskite films, the perovskite films can be easily transformed into a yellow δ-phase at room temperature in the fabrication process, a troublesome challenge for its further development. Here, ytterbium fluoride (YbF ) is introduced into the perovskite precursor for three objectives. First of all, the partial substitution of Yb for Pb in the perovskite lattice increases the tolerance factor of the perovskite lattice and facilitates the formation of the α phase. Second, YbF and DMSO in the solvent form a Lewis acid complex YbF ·DMSO, which can passivate the perovskite film, reduce defects, and improve device stability. Consequently, the YbF modified Perovskite solar cell exhibits a champion conversion efficiency of 24.53% and still maintains 90% of its initial efficiency after 60 days of air exposure under 30% relative humidity.
基于HC(NH ) (FA)的钙钛矿具有更好的光利用效率、更大的容忍因子和更高的功率转换效率（PCE），在太阳能电池应用中已被证明优于流行的基于CH NH (MA)和Cs的卤化物钙钛矿。不幸的是，受基于FA的钙钛矿薄膜内部固有缺陷的限制，在制造过程中，钙钛矿薄膜在室温下很容易转变为黄色的δ相，这对其进一步发展来说是一个棘手的挑战。在此，将氟化镱（YbF ）引入钙钛矿前驱体有三个目的。首先，Yb在钙钛矿晶格中部分取代Pb会增加钙钛矿晶格的容忍因子，并促进α相的形成。其次，溶剂中的YbF 和二甲基亚砜（DMSO）形成路易斯酸络合物YbF ·DMSO，它可以钝化钙钛矿薄膜，减少缺陷并提高器件稳定性。因此，YbF 改性的钙钛矿太阳能电池的最高转换效率为24.53%，在30%相对湿度下空气暴露60天后仍保持其初始效率的90%。
