title: Self-Host Blue-Emitting Iridium Dendrimer Containing Bipolar Dendrons for Nondoped Electrophosphorescent Devices with Superior High-Brightness Performance.
abstract: A novel self-host blue-emitting iridium dendrimer, namely, B-CzPO, has been designed and synthesized via a postdendronization route, where a bipolar carbazole/triphenylphosphine oxide hybrid is selected as the peripheral dendron instead of the p-type oligocarbazole used in unipolar analogue B-CzG2. This structural modification can render B-CzPO with more balanced charge transportation relative to that of B-CzG2. As a result of the significantly reduced efficiency roll-off, the nondoped phosphorescent organic light-emitting diodes (PhOLEDs) of B-CzPO show a superior high-brightness performance, revealing a luminous efficiency of 21.2, 16.1, and 10.5 cd/A at 1000, 5000, and 10 000 cd/m2, respectively. Compared with that of B-CzG2 (i.e., 7.8 cd/A @5000 cd/m2), more than doubled high-brightness performance is achieved for B-CzPO. The results indicate that the design of self-host phosphorescent dendrimers with a bipolar feature will be a promising strategy to develop efficient nondoped PhOLEDs suitable for high-brightness applications including general illumination and micro displays.
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, PR China.|University of the Chinese Academy of Sciences , Beijing 100049, PR China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Chemistry and Environmental Science, Hebei University , Baoding 071002, PR China.
authors.forename: Yaoming
authors.initials: Y
authors.lastname: Lu
authors.affiliation: College of Chemistry and Environmental Science, Hebei University , Baoding 071002, PR China.
authors.forename: Baoxiang
authors.initials: B
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, PR China.|University of the Chinese Academy of Sciences , Beijing 100049, PR China.
authors.forename: Shumeng
authors.initials: S
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, PR China.
authors.forename: Junqiao
authors.initials: J
authors.lastname: Ding
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, PR China.
authors.forename: Lixiang
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, PR China.
authors.forename: Xiabin
authors.initials: X
authors.lastname: Jing
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, PR China.
authors.forename: Fosong
authors.initials: F
authors.lastname: Wang
keywords: bipolar dendrons; high-brightness performance; iridium dendrimers; nondoped PhOLEDs; self-host