作者
Wei Hui,Lingfeng Chao,Hui Lu,Fei Xia,Qi Wei,Zhenhuang Su,Tingting Niu,Lei Tao,Bin Du,Deli Li,Yue Wang,Daping He,Shouwei Zuo,Bixin Li,Wei Shi,Xueqin Ran,Ping Li,Hui Zhang,Zhongbin Wu,Chenxin Ran,Lin Song,Guichuan Xing,Xingyu Gao,Jing Zhang,Yingdong Xia,Yonghua Chen,Wei Huang
摘要
The stabilization of black-phase formamidinium lead iodide (α-FAPbI3) perovskite under various environmental conditions is considered necessary for solar cells. However, challenges remain regarding the temperature sensitivity of α-FAPbI3 and the requirements for strict humidity control in its processing. Here we report the synthesis of stable α-FAPbI3, regardless of humidity and temperature, based on a vertically aligned lead iodide thin film grown from an ionic liquid, methylamine formate. The vertically grown structure has numerous nanometer-scale ion channels that facilitate the permeation of formamidinium iodide into the lead iodide thin films for fast and robust transformation to α-FAPbI3. A solar cell with a power-conversion efficiency of 24.1% was achieved. The unencapsulated cells retain 80 and 90% of their initial efficiencies for 500 hours at 85°C and continuous light stress, respectively.