title: Highly efficient multifluorenyl host materials with unsymmetrical molecular configurations and localized triplet States for green and red phosphorescent devices.
abstract: Highly efficient green and red electro-phosphorescence is achieved in devices with the host material DPESPODEF3. The multiple fluorenyl moieties of the host material are arranged such that it has an unsymmetrical molecular configuration, and its triplet-state location is tuned such that it has independent energy (ET) and charge transfer (CT) channels. As a result, DPESPODEF3 can suppress triplet-triplet annihilation and triplet-polaron quenching. In the resulting green and red phosphorescent devices, impressive external quantum efficiencies of ca. 20% and 16% and power efficiencies of ca. 75 and 20 lm W(-1) , respectively, are observed.
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education & School of Chemistry and Material Science, Heilongjiang University, 74 Xuefu Road, Harbin, 150080, PR China.
authors.forename: Chunmiao
authors.initials: C
authors.lastname: Han
authors.forename: Liping
authors.initials: L
authors.lastname: Zhu
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Fangchao
authors.initials: F
authors.lastname: Zhao
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
authors.forename: Zhaopeng
authors.initials: Z
authors.lastname: Deng
authors.forename: Dongge
authors.initials: D
authors.lastname: Ma
authors.forename: Pengfei
authors.initials: P
authors.lastname: Yan
keywords: electro-phosphorescence; organic light-emitting diodes; quenching; structure-property relationships