State Key Laboratory for Mesoscopic Physics and Department of Physics , Peking University , Beijing 100871 , P. R. China.
ACS Appl Mater Interfaces. 2019 Mar 6;11(9):9149-9155. doi: 10.1021/acsami.8b22040. Epub 2019 Feb 21.
High-efficiency organic-inorganic hybrid perovskite solar cells have experienced rapid development and attracted significant attention in recent years. However, instability to an ambient environment such as moisture is a facile challenge for the application of perovskite solar cells. Herein, 1,8-octanediammonium iodide (ODAI) is employed to construct a two-dimensional modified interface by in situ combined with residual PbI on the formamidinium lead iodide (FAPbI) perovskite surface. The ODA ion seems to lie horizontally on the surface of a three-dimensional perovskite due to its substitution for two FA ions, which could protect the bulk perovskite more effectively. The unencapsulated perovskite solar cells showed notably improved stability, which remained 92% of its initial efficiency after storing in an ambient environment for 120 days. In addition, a higher open-circuit voltage of 1.13 V compared to that of the control device (1.04 V) was obtained due to the interface energy level modification and defect passivation. A champion power conversion efficiency of 21.18% was therefore obtained with a stabilized power output of 20.64% at the maximum power point for planar perovskite solar cells.
高效的有机-无机杂化钙钛矿太阳能电池近年来发展迅速，引起了广泛关注。然而，钙钛矿太阳能电池对环境湿度等不稳定因素较为敏感，这一问题亟待解决。在此，我们采用 1,8-辛二胺碘盐（ODAI）原位与 FAPbI3 钙钛矿表面的剩余 PbI2 结合，构建二维修饰界面。由于 ODA 离子取代了两个 FA 离子，因此它似乎水平地位于三维钙钛矿的表面，从而可以更有效地保护体相钙钛矿。未封装的钙钛矿太阳能电池的稳定性显著提高，在 120 天的环境储存后，其初始效率仍保持在 92%。此外，由于界面能级修饰和缺陷钝化，器件获得了 1.13 V 的开路电压（相比于对照器件的 1.04 V）。因此，平面钙钛矿太阳能电池获得了 21.18%的冠军功率转换效率和 20.64%的最大功率点稳定功率输出。
