,Fabrication of mixed perovskite organic cation thin films via controllable cation exchange

• 作 者: Yu-Long Zhao Jin-Feng Wang Ben-Guang Zhao Chen-Chen Jia Jun-Peng Mou Lei Zhu Jian Song Xiu-Quan Gu Ying-Huai Qiang
• 机 构: School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 22111
• 出 处: 中国物理B（英文版）
• 发表日期: 2018年2期
• 关键词: organic-inorganic perovskitesolar cell morphology cation exchange drop-casting

Here in this paper,we demonstrate a facile technique for creating the mixed formamidinium (HN =CHNH3+,FA+) and methylammonium (CH3NH3+,MA+) cations in the lead iodide perovskite.This technique entails a facile drop-casting of formamidinium iodide (FAI) solutions on as-prepared MAPbI3 perovskite thin films under the controlled conditions,which leads to controllable displacement of the MA+ cations by FA+ cations in the perovskite structure at room temperature.Uniform and controllable mixed organic cation perovskite thin films without a "bi-layered" or graded structure are achieved.By applying this approach to photovoltaic devices,we are able to improve the performances of devices through extending their optical-absorption onset further into the infrared region to enhance solar-light harvesting.Additionally,this work provides a simple and efficient technique to rune the structual,electrical,and optoelectronic properties of the light-harvesting materials for high-performance perovskite solar cells.