Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan.
National Synchrotron Radiation Research Centre, Hsinchu 30076, Taiwan.
J Am Chem Soc. 2022 Aug 17;144(32):14897-14906. doi: 10.1021/jacs.2c06342. Epub 2022 Aug 4.
Two-dimensional (2D) Dion-Jacobson (DJ) perovskite solar cells (PSCs), despite their advantage in versatility of n-layer variation, are subject to poor photovoltaic efficiency, particularly in the fill factor (FF), compared to their three-dimensional counterparts. To enhance the performance of DJ PSCs, the process of growing crystals and hence the corresponding morphology of DJ perovskites are of prime importance. Herein, we report the fast nonisothermal (NIT) crystallization protocol that is previously unrecognized for 2D perovskites to significantly improve the morphology, orientation, and charge transport of the DJ perovskite films. Comprehensive mechanistic studies reveal that the NIT effect leads to the secondary crystallization stage, forming network-like channels that play a vital role in the FF's leap-forward improvement and hence the DJ PSC's performance. As a whole, the NIT crystallized PSCs demonstrate a high power conversion efficiency and an FF of up to 19.87 and 86.16%, respectively. This research thus provides new perspectives to achieve highly efficient DJ PSCs.
二维（2D）Dion-Jacobson（DJ）钙钛矿太阳能电池（PSCs）尽管在 n 层变化的通用性方面具有优势，但与三维钙钛矿相比，其光电效率较差，尤其是填充因子（FF）。为了提高 DJ PSCs 的性能，晶体生长过程以及相应的 DJ 钙钛矿形态至关重要。在这里，我们报告了一种以前未被认可的用于 2D 钙钛矿的快速非等温热结晶（NIT）协议，该协议可显著改善 DJ 钙钛矿薄膜的形态、取向和电荷输运。综合的机理研究表明，NIT 效应导致二次结晶阶段形成网状通道，在 FF 的飞跃式提高以及 DJ PSC 的性能方面发挥了重要作用。总的来说，NIT 结晶 PSCs 表现出高的功率转换效率和高达 19.87%和 86.16%的 FF。因此，这项研究为实现高效 DJ PSCs 提供了新的视角。
