title: Extremely efficient internal exciton dissociation through edge states in layered 2D perovskites.
abstract: Understanding and controlling charge and energy flow in state-of-the-art semiconductor quantum wells has enabled high-efficiency optoelectronic devices. Two-dimensional (2D) Ruddlesden-Popper perovskites are solution-processed quantum wells wherein the band gap can be tuned by varying the perovskite-layer thickness, which modulates the effective electron-hole confinement. We report that, counterintuitive to classical quantum-confined systems where photogenerated electrons and holes are strongly bound by Coulomb interactions or excitons, the photophysics of thin films made of Ruddlesden-Popper perovskites with a thickness exceeding two perovskite-crystal units (>1.3 nanometers) is dominated by lower-energy states associated with the local intrinsic electronic structure of the edges of the perovskite layers. These states provide a direct pathway for dissociating excitons into longer-lived free carriers that substantially improve the performance of optoelectronic devices.
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
authors.forename: J-C
authors.identifier: 0000-0002-3833-5792
authors.initials: JC
authors.lastname: Blancon
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA.|Department of Materials Science and Nanoengineering, Rice University, Houston, TX 77005, USA.
authors.forename: H
authors.initials: H
authors.lastname: Tsai
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
authors.forename: W
authors.initials: W
authors.lastname: Nie
authors.affiliation: Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
authors.forename: C C
authors.identifier: 0000-0001-8396-9578
authors.initials: CC
authors.lastname: Stoumpos
authors.affiliation: Fonctions Optiques pour les Technologies de l'Information (FOTON), Institut National des Sciences Appliquées (INSA) de Rennes, CNRS, UMR 6082, 35708 Rennes, France.
authors.forename: L
authors.identifier: 0000-0001-9414-8644
authors.initials: L
authors.lastname: Pedesseau
authors.affiliation: Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1, CNRS, UMR 6226, 35042 Rennes, France.
authors.forename: C
authors.identifier: 0000-0002-2017-5823
authors.initials: C
authors.lastname: Katan
authors.affiliation: Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1, CNRS, UMR 6226, 35042 Rennes, France.
authors.forename: M
authors.identifier: 0000-0001-5192-5896
authors.initials: M
authors.lastname: Kepenekian
authors.affiliation: Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
authors.forename: C M M
authors.identifier: 0000-0002-6837-9091
authors.initials: CM
authors.lastname: Soe
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: K
authors.initials: K
authors.lastname: Appavoo
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: M Y
authors.identifier: 0000-0001-5619-5722
authors.initials: MY
authors.lastname: Sfeir
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
authors.forename: S
authors.identifier: 0000-0001-5547-3647
authors.initials: S
authors.lastname: Tretiak
authors.affiliation: Department of Materials Science and Nanoengineering, Rice University, Houston, TX 77005, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Ajayan
authors.affiliation: Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.|Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA.
authors.forename: M G
authors.initials: MG
authors.lastname: Kanatzidis
authors.affiliation: Fonctions Optiques pour les Technologies de l'Information (FOTON), Institut National des Sciences Appliquées (INSA) de Rennes, CNRS, UMR 6082, 35708 Rennes, France.
authors.forename: J
authors.identifier: 0000-0002-4607-3390
authors.initials: J
authors.lastname: Even
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA. jcrochet@lanl.gov amohite@lanl.gov.
authors.forename: J J
authors.identifier: 0000-0002-9570-2173
authors.initials: JJ
authors.lastname: Crochet
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA. jcrochet@lanl.gov amohite@lanl.gov.
authors.forename: A D
authors.identifier: 0000-0001-8865-409X
authors.initials: AD
authors.lastname: Mohite