title: Structure-Property Relations of Methylamine Vapor Treated Hybrid Perovskite CH3NH3PbI3Films and Solar Cells.
abstract: The power conversion efficiency of halide perovskite solar cells is heavily dependent on the perovskite layer being sufficiently smooth and pinhole-free. It has been shown that these features can be obtained even when starting out from rough and discontinuous perovskite film by briefly exposing the film to methylamine (MA) vapor. The exact underlying physical mechanisms of this phenomenon are, however, still unclear. By investigating smooth, MA treated films based on very rough and discontinuous reference films of methylammonium triiode (MAPbI3) and considering their morphology, crystalline features, local conductive properties, and charge carrier lifetime, we unraveled the relation between their characteristic physical qualities and their performance in corresponding solar cells. We discovered that the extensive improvement in photovoltaic performance upon MA treatment is a consequence of the induced morphological enhancement of the perovskite layer together with improved electron injection into TiO2, which in fact compensates for an otherwise compromised bulk electronic quality simultaneously caused by the MA treatment.
authors.affiliation: Institute for Materials Research (IMO), Hasselt University , Wetenschapspark 1, 3590 Diepenbeek, Belgium.|Department of Physics, Clarendon Laboratory, University of Oxford , Parks Road, Oxford OX1 3PU, U.K.
authors.forename: Bert
authors.identifier: http://orcid.org/0000-0002-3830-1971
authors.initials: B
authors.lastname: Conings
authors.affiliation: Max Planck Institute for Polymer Research-Molecular Spectroscopy Group , Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Simon A
authors.initials: SA
authors.lastname: Bretschneider
authors.affiliation: Institute for Materials Research (IMO), Hasselt University , Wetenschapspark 1, 3590 Diepenbeek, Belgium.|Department of Physics, Clarendon Laboratory, University of Oxford , Parks Road, Oxford OX1 3PU, U.K.
authors.forename: Aslihan
authors.initials: A
authors.lastname: Babayigit
authors.affiliation: Electron Microscopy for Materials Research, University of Antwerp , Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gauquelin
authors.affiliation: Institute for Materials Research (IMO), Hasselt University , Wetenschapspark 1, 3590 Diepenbeek, Belgium.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Cardinaletti
authors.affiliation: X-Lab, Hasselt University , Agoralaan 1, Building D, 3590 Diepenbeek, Belgium.
authors.forename: Jean
authors.initials: J
authors.lastname: Manca
authors.affiliation: Electron Microscopy for Materials Research, University of Antwerp , Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Jo
authors.initials: J
authors.lastname: Verbeeck
authors.affiliation: Department of Physics, Clarendon Laboratory, University of Oxford , Parks Road, Oxford OX1 3PU, U.K.
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Snaith
authors.affiliation: Institute for Materials Research (IMO), Hasselt University , Wetenschapspark 1, 3590 Diepenbeek, Belgium.
authors.forename: Hans-Gerd
authors.initials: HG
authors.lastname: Boyen
keywords: MAPbI3; crystalline quality; methylamine vapor; morphology; perovskite solar cells; power conversion efficiency