title: CN-Modified Host Materials for Improved Efficiency and Lifetime in Blue Phosphorescent and Thermally Activated Delayed Fluorescent Organic Light-Emitting Diodes.
abstract: CN-modified host materials, 9-(2-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-carbazole-3-carbonitrile (o-CzCN) and 9-(3-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-carbazole-3-carbonitrile (m-CzCN), which can improve the external quantum efficiency and lifetime of both blue phosphorescent and thermally activated delayed fluorescent (TADF) emitters were developed. A molecular design approach to stabilize the molecular structure and reduce the energy gap produced two high triplet energy host materials of o-CzCN and m-CzCN compatible with the phosphorescent and TADF emitters. The new host materials lowered operation voltage, increased quantum efficiency, and elongated lifetime of both phosphorescent and TADF devices.
authors.affiliation: School of Chemical Engineering, Sungkyunkwan University , 2066, Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do 16419, Korea.
authors.forename: Sung Yong
authors.initials: SY
authors.lastname: Byeon
authors.affiliation: School of Chemical Engineering, Sungkyunkwan University , 2066, Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do 16419, Korea.
authors.forename: Ji Han
authors.initials: JH
authors.lastname: Kim
authors.affiliation: School of Chemical Engineering, Sungkyunkwan University , 2066, Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do 16419, Korea.
authors.forename: Jun Yeob
authors.identifier: http://orcid.org/0000-0002-7677-0605
authors.initials: JY
authors.lastname: Lee
keywords: blue device; delayed fluorescence; efficiency; host; lifetime