Ion‐Exchange‐Induced 2D–3D Conversion of HMA1−xFAxPbI3Cl Perovskite into a High‐Quality MA1−xFAxPbI3 Perovskite. Issue 43 (26th September 2016)

• Record Type: Journal Article
• Authors: Li, Ge; Zhang, Taiyang; Guo, Nanjie; Xu, Feng; Qian, Xufang; Zhao, Yixin
• Is Part Of: Angewandte Chemie international edition. Volume 55:Issue 43(2016)
• Page Start: 13460
• Page End: 13464
• Publication Date: 2016-09-26
• Subjects: 2D perovskites -- 2D–3D conversion -- ion exchange -- mixed-cation perovskites -- perovskite solar cells; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201606801
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: High‐quality phase‐pure MA1− x FA x PbI3 planar films (MA=methylammonium, FA=formamidinium) with extended absorption and enhanced thermal stability are difficult to deposit by regular simple solution chemistry approaches owing to crystallization competition between the easy‐to‐crystallize but unwanted δ‐FAPbI3 /MAPbI3 and FA x MA1− x PbI3 requiring rigid crystallization conditions. Here A 2D–3D conversion to transform compact 2D mixed composition HMA1− x FA x PbI3 Cl perovskite precursor films into 3D MA1− x FA x PbI3 ( x= 0.1–0.9) perovskites is presented. The designed Cl/I and H/FA(MA) ion exchange reaction induced fast transformation of compact 2D perovskite film, helping to form the phase‐pure and high quality MA1− x FA x PbI3 without δ‐FAPbI3 and MAPbI3 impurity. In all, we successfully developed a facile one‐step method to fabricate high quality phase‐pure MA1− x FA x PbI3 ( x= 0.1–0.9) perovskite films by 2D–3D conversion of HMA1− x FA x PbI3 Cl perovskite. This 2D–3D conversion is a promising strategy for lead halide perovskite fabrication. Abstract : High‐quality phase‐pure MA1− x FA x PbI3 ( x= 0.1–0.9) perovskite planar films were deposited in a facile manner by a one‐step method. 2D HMA1− x FAx PbI3 Cl perovskite (left) was transformed into 3D MA1− x FA x PbI3 perovskite (right) by ion exchange. This 2D–3D perovskite conversion is a promising strategy for fabricating mixed‐cation lead halide perovskites. MA=methylammonium, FA=formamidinium.