Ion‐Exchange‐Induced 2D–3D Conversion of HMA1−xFAxPbI3Cl Perovskite into a High‐Quality MA1−xFAxPbI3 Perovskite

• DOI: 10.1002/ange.201606801
• Publication Date: 2016-09-26T09:26:45Z
• Authors: Ge Li; Taiyang Zhang; Nanjie Guo; Feng Xu; Xufang Qian; Yixin Zhao
• Keywords: Formamidinium

High-quality phase-pure MA1−xFAxPbI3 planar films (MA=methylammonium, FA=formamidinium) with extended absorption and enhanced thermal stability are difficult to deposit by regular simple solution chemistry approaches owing crystallization competition between the easy-to-crystallize but unwanted δ-FAPbI3/MAPbI3 FAxMA1−xPbI3 requiring rigid conditions. Here A 2D–3D conversion transform compact 2D mixed composition HMA1−xFAxPbI3Cl perovskite precursor into 3D (x=0.1–0.9) perovskites is presented. The designed Cl/I H/FA(MA) ion exchange reaction induced fast transformation of film, helping form high quality without δ-FAPbI3 MAPbI3 impurity. In all, we successfully developed a facile one-step method fabricate perovskite. This promising strategy for lead halide fabrication.