title: Emission Enhancement and Intermittency in Polycrystalline Organolead Halide Perovskite Films.
abstract: Inorganic-organic halide organometal perovskites have demonstrated very promising performance for opto-electronic applications, such as solar cells, light-emitting diodes, lasers, single-photon sources, etc. However, the little knowledge on the underlying photophysics, especially on a microscopic scale, hampers the further improvement of devices based on this material. In this communication, correlated conventional photoluminescence (PL) characterization and wide-field PL imaging as a function of time are employed to investigate the spatially- and temporally-resolved PL in CH₃NH₃PbI3-xClx perovskite films. Along with a continuous increase of the PL intensity during light soaking, we also observe PL blinking or PL intermittency behavior in individual grains of these films. Combined with significant suppression of PL blinking in perovskite films coated with a phenyl-C61-butyric acid methyl ester (PCBM) layer, it suggests that this PL intermittency is attributed to Auger recombination induced by photoionized defects/traps or mobile ions within grains. These defects/traps are detrimental for light conversion and can be effectively passivated by the PCBM layer. This finding paves the way to provide a guideline on the further improvement of perovskite opto-electronic devices.
authors.affiliation: Organic and Hybrid Electronics, Macromolecular Chemistry I, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. cheng.li@uni-bayreuth.de.
authors.forename: Cheng
authors.initials: C
authors.lastname: Li
authors.affiliation: Organic and Hybrid Electronics, Macromolecular Chemistry I, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. s2yuzhon@stmail.uni-bayreuth.de.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhong
authors.affiliation: Experimental Physics IV and Bayreuth Institute of Macromolecular Research, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. Carlos.Melo@uni-bayreuth.de.|Centre for Bioinformatics and Photonics-CIBioFi, Calle 13 No. 100-00, Edificio 320 No. 1069 and Departamento de Fisica, Universidad del Valle, Cali 760032, Colombia. Carlos.Melo@uni-bayreuth.de.
authors.forename: Carlos Andres Melo
authors.initials: CA
authors.lastname: Luna
authors.affiliation: Experimental Physics II, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. thomas.unger@uni-bayreuth.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Unger
authors.affiliation: Experimental Physics IV and Bayreuth Institute of Macromolecular Research, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. konstantin.deichsel@gmx.de.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Deichsel
authors.affiliation: Organic and Hybrid Electronics, Macromolecular Chemistry I, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. anna.graeser@uni-bayreuth.de.
authors.forename: Anna
authors.initials: A
authors.lastname: Gräser
authors.affiliation: Experimental Physics IV and Bayreuth Institute of Macromolecular Research, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. juergen.koehler@uni-bayreuth.de.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Köhler
authors.affiliation: Experimental Physics II, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. anna.koehler@uni-bayreuth.de.
authors.forename: Anna
authors.initials: A
authors.lastname: Köhler
authors.affiliation: Experimental Physics IV and Bayreuth Institute of Macromolecular Research, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. richard.hildner@uni-bayreuth.de.
authors.forename: Richard
authors.initials: R
authors.lastname: Hildner
authors.affiliation: Organic and Hybrid Electronics, Macromolecular Chemistry I, University of Bayreuth, Universitätstr. 30, Bayreuth 95447, Germany. sven.huetttner@uni-bayreuth.de.
authors.forename: Sven
authors.initials: S
authors.lastname: Huettner
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry*; D007854:Lead / Q000737:chemistry*; D008027:Light; D010087:Oxides / Q000737:chemistry*; D017785:Photons; D014025:Titanium / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D010087:Oxides; C059910:perovskite; D007854:Lead; D014025:Titanium
keywords: Auger recombination; Methylammonium Lead Halide; blinking; intermittency; ion migration; methylammonium lead iodide; passivation; perovskite solar cells; photoluminescence