title: Solvent and Intermediate Phase as Boosters for the Perovskite Transformation and Solar Cell Performance.
abstract: High power conversion efficiency and device stabilization are two major challenges for CH3NH3PbI3 (MAPbI3) perovskite solar cells to be commercialized. Herein, we demonstrate a diffusion-engineered perovskite synthesis method using MAI/ethanol dipping, and compared it to the conventional synthesis method from MAI/iso-propanol. Diffusion of MAI/C2H5OH into the PbCl2 film was observed to be more favorable than that of MAI/C3H7OH. Facile perovskite conversion from ethanol and highly-crystalline MAPbI3 with minimized impurities boosted the efficiency from 5.86% to 9.51%. Additionally, we further identified the intermediates and thereby the reaction mechanisms of PbCl2 converting into MAPbI3. Through straightforward engineering to enhance the surface morphology as well as the crystallinity of the perovskite with even faster conversion, an initial power conversion efficiency of 11.23% was obtained, in addition to superior stability after 30 days under an ambient condition.
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
authors.forename: Jinhyun
authors.initials: J
authors.lastname: Kim
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
authors.forename: Taehyun
authors.initials: T
authors.lastname: Hwang
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
authors.forename: Sangheon
authors.initials: S
authors.lastname: Lee
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
authors.forename: Byungho
authors.initials: B
authors.lastname: Lee
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
authors.forename: Jaewon
authors.initials: J
authors.lastname: Kim
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
authors.forename: Gil Su
authors.initials: GS
authors.lastname: Jang
authors.affiliation: Nano Mechanical Systems Research Division, Department of Nano Mechanics, Korea Institute of Machinery &Materials (KIMM), Daejeon 305-343, Korea.
authors.forename: Seunghoon
authors.initials: S
authors.lastname: Nam
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
authors.forename: Byungwoo
authors.initials: B
authors.lastname: Park