title: Charge Carrier Lifetimes Exceeding 15 μs in Methylammonium Lead Iodide Single Crystals.
abstract: The charge carrier lifetime in organic-inorganic perovskites is one of the most important parameters for modeling and design of solar cells and other types of devices. In this work, we use CH3NH3PbI3 single crystal as a model system to study optical absorption, charge carrier generation, and recombination lifetimes. We show that commonly applied photoluminescence lifetime measurements may dramatically underestimate the intrinsic carrier lifetime in CH3NH3PbI3, which could be due to severe charge recombination at the crystal surface and/or fast electron-hole recombination close to the surface. By using the time-resolved microwave conductivity technique, we investigated the lifetime of free mobile charges inside the crystals. Most importantly, we find that for homogeneous excitation throughout the crystal, the charge carrier lifetime exceeds 15 μs. This means that the diffusion length in CH3NH3PbI3 can be as large as 50 μm if it is no longer limited by the dimensions of the crystallites.
authors.affiliation: Optoelectronic Materials Section, Department of Chemical Engineering, Delft University of Technology , 2628 BL Delft, The Netherlands.
authors.forename: Yu
authors.initials: Y
authors.lastname: Bi
authors.affiliation: Optoelectronic Materials Section, Department of Chemical Engineering, Delft University of Technology , 2628 BL Delft, The Netherlands.
authors.forename: Eline M
authors.initials: EM
authors.lastname: Hutter
authors.affiliation: Department of Mechanical and Materials Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln , Nebraska 68588-0656, United States.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Department of Mechanical and Materials Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln , Nebraska 68588-0656, United States.
authors.forename: Qingfeng
authors.initials: Q
authors.lastname: Dong
authors.affiliation: Department of Mechanical and Materials Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln , Nebraska 68588-0656, United States.
authors.forename: Jinsong
authors.initials: J
authors.lastname: Huang
authors.affiliation: Optoelectronic Materials Section, Department of Chemical Engineering, Delft University of Technology , 2628 BL Delft, The Netherlands.
authors.forename: Tom J
authors.initials: TJ
authors.lastname: Savenije