Fabrication of Efficient Low-Bandgap Perovskite Solar Cells by Combining Formamidinium Tin Iodide with Methylammonium Lead Iodide

作者：Wei‐Qiang Liao, Dewei Zhao, Yue Yu, Niraj Shrestha, Kiran Ghimire, Corey R. Grice, Changlei Wang, Yuqing Xiao, Alexander J. Cimaroli, Randy J. Ellingson, Nikolas J. Podraza, Kai Zhu, Ren-Gen Xiong, Yanfa Yan · 发表于：Journal of the American Chemical Society · 年份：2016 · DOI：10.1021/jacs.6b08337 · 被引用次数：435 · 研究领域：Perovskite Materials and Applications、Conducting polymers and applications、Solid-state spectroscopy and crystallography

Mixed tin (Sn)-lead (Pb) perovskites with high Sn content exhibit low bandgaps suitable for fabricating the bottom cell of perovskite-based tandem solar cells. In this work, we report on the fabrication of efficient mixed Sn-Pb perovskite solar cells using precursors combining formamidinium tin iodide (FASnI3) and methylammonium lead iodide (MAPbI3). The best-performing cell fabricated using a (FASnI3)0.6(MAPbI3)0.4 absorber with an absorption edge of ∼1.2 eV achieved a power conversion efficiency (PCE) of 15.08 (15.00)% with an open-circuit voltage of 0.795 (0.799) V, a short-circuit current density of 26.86(26.82) mA/cm(2), and a fill factor of 70.6(70.0)% when measured under forward (reverse) voltage scan. The average PCE of 50 cells we have fabricated is 14.39 ± 0.33%, indicating good reproducibility.