title: Polyethylenimine Ethoxylated-Mediated All-Solution-Processed High-Performance Flexible Inverted Quantum Dot-Light-Emitting Device.
abstract: We report on an all-solution-processed fabrication of highly efficient green quantum dot-light-emitting diodes (QLEDs) with an inverted architecture, where an interfacial polymeric surface modifier of polyethylenimine ethoxylated (PEIE) is inserted between a quantum dot (QD) emitting layer (EML) and a hole transport layer (HTL), and a MoOxhole injection layer is solution deposited on top of the HTL. Among the inverted QLEDs with varied PEIE thicknesses, the device with an optimal PEIE thickness of 15.5 nm shows record maximum efficiency values of 65.3 cd/A in current efficiency and 15.6% in external quantum efficiency (EQE). All-solution-processed fabrication of inverted QLED is further implemented on a flexible platform by developing a high-performing transparent conducting composite film of ZnO nanoparticles-overcoated on Ag nanowires. The resulting flexible inverted device possesses 35.1 cd/A in current efficiency and 8.4% in EQE, which are also the highest efficiency values ever reported in flexible QLEDs.
authors.forename: Daekyoung
authors.initials: D
authors.lastname: Kim
authors.forename: Yan
authors.initials: Y
authors.lastname: Fu
authors.forename: Sunho
authors.initials: S
authors.lastname: Kim
authors.forename: Woosuk
authors.initials: W
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Hongik University , Seoul 121-791, Korea.
authors.forename: Ki-Heon
authors.initials: KH
authors.lastname: Lee
authors.forename: Ho Kyoon
authors.initials: HK
authors.lastname: Chung
authors.forename: Hoo-Jeong
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Hongik University , Seoul 121-791, Korea.
authors.forename: Heesun
authors.identifier: 0000-0002-2827-2070
authors.initials: H
authors.lastname: Yang
authors.forename: Heeyeop
authors.initials: H
authors.lastname: Chae
keywords: all-solution-processed; flexible device; inverted architecture; quantum dot-light-emitting diode