title: Interfacial electronic structures revealed at the rubrene/CH3NH3PbI3interface.
abstract: The electronic structures of rubrene films deposited on CH3NH3PbI3perovskite have been investigated using in situ ultraviolet photoelectron spectroscopy (UPS) and X-ray photoelectron spectroscopy (XPS). It was found that rubrene molecules interacted weakly with the perovskite substrate. Due to charge redistribution at their interface, a downward 'band bending'-like energy shift of ∼0.3 eV and an upward band bending of ∼0.1 eV were identified at the upper rubrene side and the CH3NH3PbI3substrate side, respectively. After the energy level alignment was established at the rubrene/CH3NH3PbI3interface, its highest occupied molecular orbital (HOMO)-valence band maximum (VBM) offset was found to be as low as ∼0.1 eV favoring the hole extraction with its lowest unoccupied molecular orbital (LUMO)-conduction band minimum (CBM) offset as large as ∼1.4 eV effectively blocking the undesired electron transfer from perovskite to rubrene. As a demonstration, simple inverted planar solar cell devices incorporating rubrene and rubrene/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hole transport layers (HTLs) were fabricated in this work and yielded a champion power conversion efficiency of 8.76% and 13.52%, respectively. Thus, the present work suggests that a rubrene thin film could serve as a promising hole transport layer for efficient perovskite-based solar cells.
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn and University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China.
authors.forename: Gengwu
authors.initials: G
authors.lastname: Ji
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn and University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China.
authors.forename: Guanhaojie
authors.initials: G
authors.lastname: Zheng
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn.
authors.forename: Fei
authors.initials: F
authors.lastname: Song
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn and University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China.
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn.
authors.forename: Kongchao
authors.initials: K
authors.lastname: Shen
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn.
authors.forename: Yingguo
authors.initials: Y
authors.lastname: Yang
authors.affiliation: High Magnetic Field Laboratory, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei, 230031, Anhui, P. R. China. lcao@hmfl.ac.cn.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Xiong
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2019 Jia Luo Road, Shanghai, 201800, P. R. China. gaoxingyu@sinap.ac.cn.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Gao
authors.affiliation: High Magnetic Field Laboratory, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei, 230031, Anhui, P. R. China. lcao@hmfl.ac.cn.
authors.forename: Liang
authors.identifier: http://orcid.org/0000-0001-7453-7060
authors.initials: L
authors.lastname: Cao
authors.affiliation: Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia. D.Qi@latrobe.edu.au.
authors.forename: Dong-Chen
authors.initials: DC
authors.lastname: Qi