Author:
Hou 候 Minna 敏娜,Guo 郭 Xu 旭,Han 韩 Meidouxue 梅斗雪,Zhao 赵 Juntao 均陶,Wang 王 Zhiyuan 志元,Ding 丁 Yi 毅,Hou 侯 Guofu 国付,Zhang 张 Zongsheng 宗胜,Han 韩 Xiaoping 小平
Abstract
It is highly desirable to enhance the long-term stability of perovskite solar cells (PSCs) so that this class of photovoltaic cells can be effectively used for the commercialization purposes. In this contribution, attempts have been made to use the two-step sequential method to dope EuBr2 into FAMAPbI3 perovskite to promote the stability. It is shown that the device durability at 85 °C in air with RH of 20%–40% is improved substantially, and simultaneously the champion device efficiency of 23.04% is achieved. The enhancement in stability is attributed to two points: (i) EuBr2 doping effectively inhibits the decomposition and α–δ phase transition of perovskite under ambient environment, and (ii) EuBr2 aggregates in the oxidized format of Eu(BrO3)3 at perovskite grain boundaries and surface, hampering humidity erosion and mitigates degradation through coordination with H2O.