title: Tailoring Mixed-Halide, Wide-Gap Perovskites via Multistep Conversion Process.
abstract: Wide-band-gap mixed-halide CH3NH3PbI3-XBrX-based solar cells have been prepared by means of a sequential spin-coating process. The spin-rate for PbI2 as well as its repetitive deposition are important in determining the cross-sectional shape and surface morphology of perovskite, and, consequently, J-V performance. A perovskite solar cell converted from PbI2 with a dense bottom layer and porous top layer achieved higher device performance than those of analogue cells with a dense PbI2 top layer. This work demonstrates a facile way to control PbI2 film configuration and morphology simply by modification of spin-coating parameters without any additional chemical or thermal post-treatment.
authors.affiliation: Center for Individual Nanoparticle Functionality, Department of Physics, Technical University of Denmark , Building 311, Fysikvej, DK-2800 Kgs, Lyngby, Denmark.|Department of Chemical Engineering, Stanford University , Stanford, California 94305-5025, United States.
authors.forename: Dowon
authors.initials: D
authors.lastname: Bae
authors.affiliation: Department of Chemical Engineering, Stanford University , Stanford, California 94305-5025, United States.
authors.forename: Axel
authors.initials: A
authors.lastname: Palmstrom
authors.affiliation: Department of Materials Science and Engineering, Stanford University , Stanford, California 94305-4034, United States.
authors.forename: Katherine
authors.initials: K
authors.lastname: Roelofs
authors.affiliation: Center for Individual Nanoparticle Functionality, Department of Physics, Technical University of Denmark , Building 311, Fysikvej, DK-2800 Kgs, Lyngby, Denmark.
authors.forename: Bastian
authors.initials: B
authors.lastname: Mei
authors.affiliation: Center for Individual Nanoparticle Functionality, Department of Physics, Technical University of Denmark , Building 311, Fysikvej, DK-2800 Kgs, Lyngby, Denmark.
authors.forename: Ib
authors.initials: I
authors.lastname: Chorkendorff
authors.affiliation: Department of Chemical Engineering, Stanford University , Stanford, California 94305-5025, United States.
authors.forename: Stacey F
authors.initials: SF
authors.lastname: Bent
authors.affiliation: Center for Individual Nanoparticle Functionality, Department of Physics, Technical University of Denmark , Building 311, Fysikvej, DK-2800 Kgs, Lyngby, Denmark.
authors.forename: Peter C K
authors.initials: PC
authors.lastname: Vesborg
keywords: lead-halide; multistep deposition; organic−inorganic hybrids; photovoltaics; spin-coating