Synthesis of pyrimidine-cored host materials bearing phenylcarbazole for efficient yellow phosphorescent devices: effect of linkage position

Abstract

Two isomeric host materials were synthesized and their photophysical properties and device performances were investigated. In particular, para-substituted pPDPC exhibited the most intense efficiency regardless of the low triplet energy compared to that of meta-substituted mPDPC. The EQE of the pPDPC device reached as high as 22.3% with a yellow color coordinate of (0.49, 0.50).