title: Efficient CdSe/CdS quantum dot light-emitting diodes using a thermally polymerized hole transport layer.
abstract: We report multilayer nanocrystal quantum dot light-emitting diodes (QD-LEDs) fabricated by spin-coating a monolayer of colloidal CdSe/CdS nanocrystals on top of thermally polymerized solvent-resistant hole-transport layers (HTLs). We obtain high-quality QD layers of controlled thickness (down to submonolayer) simply by spin-coating QD solutions directly onto the HTL. The resulting QD-LEDs exhibit narrow ( approximately 30 nm, fwhm) electroluminescence from the QDs with virtually no emission from the organic matrix at any voltage. Using multiple spin-on HTLs improves the external quantum efficiency of the QD-LEDs to approximately 0.8% at a brightness of 100 cd/m(2) (with a maximum brightness over 1,000 cd/m(2)). We conclude that QD-LEDs could be made more efficient by further optimization of the organic semiconductors.
authors.affiliation: Department of Chemistry, University of Washington, Box 351700, Seattle, 98195-1700, USA.
authors.forename: Jialong
authors.initials: J
authors.lastname: Zhao
authors.forename: Julie A
authors.initials: JA
authors.lastname: Bardecker
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Munro
authors.forename: Michelle S
authors.initials: MS
authors.lastname: Liu
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Niu
authors.forename: I-Kang
authors.initials: IK
authors.lastname: Ding
authors.forename: Jingdong
authors.initials: J
authors.lastname: Luo
authors.forename: Baoquan
authors.initials: B
authors.lastname: Chen
authors.forename: Alex K-Y
authors.initials: AK
authors.lastname: Jen
authors.forename: David S
authors.initials: DS
authors.lastname: Ginger