title: Highly efficient tandem organic light-emitting devices utilizing the connecting structure based on n-doped electron-transport layer/HATCN/hole-transport layer.
abstract: In this work, we conducted studies of tandem organic light-emitting devices (OLEDs) based on the connecting structure consisting of n-doped electron-transport layer (n-ETL)/1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HATCN)/hole-transport layer. We investigated effects of different n-ETL materials and different HATCN thicknesses on characteristics of tandem OLEDs. Results show that the tandem OLEDs with n-BPhen and a 20 nm layer of HATCN in the connecting structure exhibited the best performance. With these, highly efficient and bright green phosphorescent two-emitting-unit tandem OLEDs, with drive voltages significantly lower than twice that of the single-unit benchmark device and current efficiencies higher than twice that of the single-unit benchmark device, were demonstrated.
authors.forename: Yi-Lin
authors.initials: YL
authors.lastname: Wu
authors.forename: Chien-Yu
authors.initials: CY
authors.lastname: Chen
authors.forename: Yi-Hsiang
authors.initials: YH
authors.lastname: Huang
authors.forename: Yin-Jui
authors.initials: YJ
authors.lastname: Lu
authors.forename: Cheng-Hsu
authors.initials: CH
authors.lastname: Chou
authors.forename: Chung-Chih
authors.initials: CC
authors.lastname: Wu