121st General Meeting of the KCS

Type Poster Presentation
Area Physical Chemistry
Room No. Event Hall
Time 4월 20일 (금요일) 11:00~12:30
Code PHYS.P-197
Subject Phosphorescence Efficiency of Cyclometalated Iridium Complex by Substituted o-Carboranes - A Computational Study
Authors Saibal Jana, Sang Uck Lee1,*
Department of Bionano Technology, Hanyang University ERICA, Korea
1Department of Bio-Nano Engineering, Hanyang University, Korea
Abstract Cyclometalated iridium (III) complexes are widely used as highly efficient color-tunable emitters in organic light emitting diodes (OLEDs) and solid-state lightning due to their excellent photophysical properties such as good color purity, high quantum efficiency, relatively short phosphorescence lifetime, and high thermal stability. The successful demonstration of the iridium (III) cyclometalates in OLED applications is mainly attributed to the facile control over the emissive lowest-lying triplet excited states (3MLCT and 3ππ*) by modifying the electronic structure of the cyclometalating (C^N) ligand. Introduction of substituents with different electronic effects (inductive and/or conjugation effects) on the C^N ligand has enabled the control of the energy levels for the HOMOs and LUMOs that determine the excited-state energy. Owing to growing interest in blue emitters for OLED applications, the wide band gap of the iridium (III) cyclometalates have received great attention. The modification of the C^N ligands is also an alternative way to increase the band gap energy. As a novel substituent on the C^N ligand, o-carborane (1,2-closo-C2B10H12) attracts growing interest because it may serve not only as a steric auxiliary to suppress quenching of solid state emission but also offer an electronic effect to alter the band gap and phosphorescence efficiency. The focus of this presentation is to explain the theoretical insight into the crucial role in controlling phosphorescence efficiency of the substituted o-carborane iridium (III) cyclometalates.
E-mail saibal@cms.hanyang.ac.kr