title: Diboron complexes with bis-spiro structures as high-performance blue emitters for OLEDs.
abstract: To construct high-performance organoboron-based blue emitters for electroluminescent (EL) devices, two diboron complexes have been synthesized through the chelation of 2-(1-phenyl-1H-benzo[d]imidazole-2-yl)phenol or 2-(2-pyridyl)phenol ligands with both boron atoms of the 9,10-diboraanthracene group. These complexes exhibit bright blue emissions in solution and in solid films with fluorescence quantum yields over 0.42, which benefit from their bis-spiro structures. In addition, they possess high thermal decomposition (>410 °C) and glass transition (>163 °C) temperatures. Moreover, they are excellent ambipolar transporting materials with high and balanced mobilities (>10(-4) cm(2) V(-1) s(-1)) for holes and electrons. Due to these excellent properties, the EL devices adopting these complexes as non-doped emitting layers emit blue light and exhibit low turn-on voltages (<3.2 V), high luminance (up to 9041 cd m(-2)), as well as high current (up to 7.01 cd A(-1)) and power efficiencies (up to 7.58 lm W(-1)). To the best of our knowledge, these devices are so far the brightest and most efficient blue devices based on four-coordinate organoboron emitters.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, International Joint Research Laboratory of Nano-Micro Architecture Chemistry, College of Chemistry, Jilin University, Changchun 130012, P. R. China. zuolunzhang@jlu.edu.cn.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhang
authors.forename: Zuolun
authors.initials: Z
authors.lastname: Zhang
authors.forename: Kaiqi
authors.initials: K
authors.lastname: Ye
authors.forename: Jingying
authors.initials: J
authors.lastname: Zhang
authors.forename: Hongyu
authors.initials: H
authors.lastname: Zhang
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang