title: Synergy of ammonium chloride and moisture on perovskite crystallization for efficient printable mesoscopic solar cells.
abstract: Organometal lead halide perovskites have been widely used as the light harvester for high-performance solar cells. However, typical perovskites of methylammonium lead halides (CH3NH3PbX3, X=Cl, Br, I) are usually sensitive to moisture in ambient air, and thus require an inert atmosphere to process. Here we demonstrate a moisture-induced transformation of perovskite crystals in a triple-layer scaffold of TiO2/ZrO2/Carbon to fabricate printable mesoscopic solar cells. An additive of ammonium chloride (NH4Cl) is employed to assist the crystallization of perovskite, wherein the formation and transition of intermediate CH3NH3X·NH4PbX3(H2O)2(X=I or Cl) enables high-quality perovskite CH3NH3PbI3crystals with preferential growth orientation. Correspondingly, the intrinsic perovskite devices based on CH3NH3PbI3achieve an efficiency of 15.6% and a lifetime of over 130 days in ambient condition with 30% relative humidity. This ambient-processed printable perovskite solar cell provides a promising prospect for mass production, and will promote the development of perovskite-based photovoltaics.
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Yaoguang
authors.identifier: 0000-0003-4794-8213
authors.initials: Y
authors.lastname: Rong
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Hou
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Anyi
authors.identifier: 0000-0002-8142-853X
authors.initials: A
authors.lastname: Mei
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Linfeng
authors.initials: L
authors.lastname: Liu
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Han