Quasi‐2D Bilayer Surface Passivation for High Efficiency Narrow Bandgap Perovskite Solar Cells

作者：Danni Yu, Qi Wei, Hansheng Li, Junhan Xie, Xianyuan Jiang, Ting Pan, Hao Wang, Mengling Pan, Wenjia Zhou, Weimin Liu, Philip C. Y. Chow, Zhijun Ning · 发表于：Angewandte Chemie International Edition · 年份：2022 · DOI：10.1002/anie.202202346 · 被引用次数：80 · 研究领域：Perovskite Materials and Applications、Quantum Dots Synthesis And Properties、Chalcogenide Semiconductor Thin Films

Abstract The combination of comprehensive surface passivation and effective interface carriers transfer plays a critical role in high‐performance perovskite solar cells. A 2D structure is an important approach for surface passivation of perovskite film, however, its large band gap could compromise carrier transfer. Herein, we synthesize a new molecule 2‐thiopheneethylamine thiocyanate (TEASCN) for the construction of bilayer quasi‐2D structure precisely on a tin‐lead mixed perovskite surface. This bilayer structure can passivate the perovskite surface and ensure effective carriers transfer simultaneously. As a result, the open‐circuit voltage ( V oc ) of the device is increased without sacrificing short‐circuit current density ( J sc ), giving rise to a high certified efficiency from a credible third‐party certification of narrow band gap perovskite solar cells. Furthermore, theoretical simulation indicates that the inclusion of TEASCN makes the bilayer structure thermodynamically more stable, which provides a strategy to tailor the number of layers of quasi‐2D perovskite structures.