title: High-Work-Function Molybdenum Oxide Hole Extraction Contacts in Hybrid Organic-Inorganic Perovskite Solar Cells.
abstract: We investigate the effect of high work function contacts in halide perovskite absorber-based photovoltaic devices. Photoemission spectroscopy measurements reveal that band bending is induced in the absorber by the deposition of the high work function molybdenum trioxide (MoO3). We find that direct contact between MoO3and the perovskite leads to a chemical reaction, which diminishes device functionality. Introducing an ultrathin spiro-MeOTAD buffer layer prevents the reaction, yet the altered evolution of the energy levels in the methylammonium lead iodide (MAPbI3) layer at the interface still negatively impacts device performance.
authors.affiliation: Department of Electrical Engineering, Princeton University , Princeton, New Jersey 08544, United States.|National Renewable Energy Laboratory , Golden, Colorado 80401, United States.
authors.forename: Philip
authors.initials: P
authors.lastname: Schulz
authors.affiliation: Department of Electrical Engineering, Princeton University , Princeton, New Jersey 08544, United States.
authors.forename: Jan O
authors.initials: JO
authors.lastname: Tiepelt
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Christians
authors.affiliation: Department of Materials and Interfaces, Weizmann Institute of Science , Rehovot 76100, Israel.
authors.forename: Igal
authors.initials: I
authors.lastname: Levine
authors.affiliation: Department of Materials and Interfaces, Weizmann Institute of Science , Rehovot 76100, Israel.
authors.forename: Eran
authors.initials: E
authors.lastname: Edri
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.|Department of Electrical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Erin M
authors.initials: EM
authors.lastname: Sanehira
authors.affiliation: Department of Materials and Interfaces, Weizmann Institute of Science , Rehovot 76100, Israel.
authors.forename: Gary
authors.initials: G
authors.lastname: Hodes
authors.affiliation: Department of Materials and Interfaces, Weizmann Institute of Science , Rehovot 76100, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Cahen
authors.affiliation: Department of Electrical Engineering, Princeton University , Princeton, New Jersey 08544, United States.
authors.forename: Antoine
authors.initials: A
authors.lastname: Kahn
keywords: band offsets; charge carrier transport; electronic structures/processes/mechanisms; hybrid materials; photoemission spectroscopy; photovoltaic devices