A computational study of tri-s-triazine-based molecules as ambipolar host materials for phosphorescent blue emitters: effective geometric and electronic tuning

作者：Li, Jing; Nie, Zhaomin; Li, Hai; Peng, Yiming; Wang, Ziyuan; Mai, Zhirui; Zheng, Wenxu^*

来源：Journal of Materials Chemistry C, 2015, 3(19): 4859-4867.

DOI：10.1039/c4tc02269f

• HIGH TRIPLET ENERGY
• EFFICIENT BLUE
• DERIVATIVES
• DESIGN
• ELECTROPHOSPHORESCENCE
• PROPERTY
• DEVICES
• SINGLET

A series of host molecules for blue electrophosphorescence have been designed using density functional theory by incorporating carbazole and tri-s-triazine. It is found that the carbazole ring should be coplanar with a tri-s-triazine ring for obtaining high triplet energy (E-T). Results obtained from the electronic structure calculations show that the triplet energy, HOMO and LUMO energy levels and reorganization energy (lambda) of the designed hosts can be modulated efficiently through different substitution patterns. This study provides theoretical insights into the nature of host molecules, and shows that the designed molecules with an NH2 group in a tri-s-triazine ring and an alkyl group in a carbazole ring can meet the requirements of the host materials for blue emitting phOLEDs owing to their high E-T value, appropriate energy level alignment, balanced charge transfer, high triplet exciton-formation fraction (chi(T)) and small difference between S-1 and T-1 excitation energy (Delta E-ST).

• 出版日期2015
• 单位华南农业大学