Zhang Xuehao, Hao Yang, Li Shiqi, Ren Jingkun, Wu Yukun, Sun Qinjun, Cui Yanxia, Hao Yuying
College of Physics and Optoelectronics, Key Lab of Advanced Transducers and Intelligent Control System, Taiyuan University of Technology, Taiyuan 030024, China.
J Phys Chem Lett. 2022 Jan 13;13(1):118-129. doi: 10.1021/acs.jpclett.1c03807. Epub 2021 Dec 28.
Low-bandgap tin-lead mixed perovskites (PVKs) are necessary for all-perovskite tandem solar cells. This work proposes a multifunctional sandwich structure with 2-chloroethylamine (CEA) as the top and bottom interface layer and perovskite as the core layer. The sandwich structured CEA allows large ClCHCHNH and small Cl to diffuse into the crystal lattice and grain boundaries of perovskites, endowing an excellent antioxidation property by forming Sn(0), coordinating with SnI, and controlling the perovskite crystallization process. Moreover, the energy level alignment at the interface of the perovskite and transport layer becomes more matched. As a result, the CEA-modified champion device acquires a power conversion efficiency of 18.13% with an open-circuit voltage of 0.82 V and a short-circuit current density of 30.06 mA cm. Meanwhile, the environmental stability of CEA-modified devices is substantially enhanced. This work introduces a new strategy for improving the performance and stability of tin-lead mixed perovskite solar cells.
低带隙锡铅混合钙钛矿对于全钙钛矿串联太阳能电池来说是必不可少的。这项工作提出了一种多功能三明治结构，以2-氯乙胺（CEA）作为顶部和底部界面层，钙钛矿作为核心层。这种三明治结构的CEA允许大的ClCHCHNH和小的Cl扩散到钙钛矿的晶格和晶界中，通过形成Sn(0)、与SnI配位以及控制钙钛矿的结晶过程，赋予其优异的抗氧化性能。此外，钙钛矿与传输层界面处的能级排列变得更加匹配。结果，经CEA改性的冠军器件获得了18.13%的功率转换效率，开路电压为0.82 V，短路电流密度为30.06 mA cm。同时，CEA改性器件的环境稳定性得到了显著提高。这项工作引入了一种提高锡铅混合钙钛矿太阳能电池性能和稳定性的新策略。
