title: Efficient hybrid mesoscopic solar cells with morphology-controlled CH3NH3PbI3-xClx derived from two-step spin coating method.
abstract: A morphology-controlled CH3NH3PbI3-xClx film is synthesized via two-step solution deposition by spin-coating a mixture solution of CH3NH3Cl and CH3NH3I onto the TiO2/PbI2 film for the first time. It is revealed that the existence of CH3NH3Cl is supposed to result in a preferential growth along the [110] direction of perovskite, which can improve both the crystallinity and surface coverage of perovskite and reduce the pinholes. Furthermore, the formation process of CH3NH3PbI3-xClx perovskite is explored, in which intermediates containing chlorine are suggested to exist. 13.12% of power conversion efficiency has been achieved for the mesoscopic cell, higher than 12.08% of power conversion efficiency of the devices fabricated without CH3NH3Cl via the same process. The improvement mainly lies in the increasing open-circuit photovoltage which is ascribed to the reduction of reverse saturation current density.
authors.affiliation: Key Laboratory for Renewable Energy, Chinese Academy of Sciences, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics, Chinese Academy of Sciences , Zhongguancun South Third Street 8, Haidian District, Beijing 100190, China.
authors.forename: Yuzhuan
authors.initials: Y
authors.lastname: Xu
authors.forename: Lifeng
authors.initials: L
authors.lastname: Zhu
authors.forename: Jiangjian
authors.initials: J
authors.lastname: Shi
authors.forename: Songtao
authors.initials: S
authors.lastname: Lv
authors.forename: Xin
authors.initials: X
authors.lastname: Xu
authors.forename: Junyan
authors.initials: J
authors.lastname: Xiao
authors.forename: Juan
authors.initials: J
authors.lastname: Dong
authors.forename: Huijue
authors.initials: H
authors.lastname: Wu
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Luo
authors.forename: Dongmei
authors.initials: D
authors.lastname: Li
authors.forename: Qingbo
authors.initials: Q
authors.lastname: Meng
keywords: mixed-halide lead perovskite; morphology-control; perovskite formation process; preferential-growth; solar cells; two-step spin coating