Novel Deep-Blue Hybridized Local and Charge-Transfer Host Emitter for High-Quality Fluorescence/Phosphor Hybrid Quasi-White Organic Light-Emitting Diode

A new hybrid local and charge transfer (HLCT) molecule 2TPA-PPI is obtained for constructing the high-performance organic light-emitting diodes (OLEDs) in this work. 2TPA-PPI possesses the sufficient emission/charge-transporting properties, thus it is used as a neat emitter achieving an efficient deep-blue OLED with very high external quantum efficiency (EQE) up to 10.7%, as well as a multi-functional emitting host matrix constructing the high-performance phosphorescent OLEDs. More importantly, a high-efficiency candle light-style OLED adopting the HLCT/phosphor hybrid strategy is realized, where 2TPA-PPI acts as not only a blue emitter, but also a universal host sensitizing both yellow and red phosphors. This quasi-white OLED represents almost the highest EQE/PE level of 25.2%/49.7 lm W-1 at the practical luminance level of 1000 cd m(-2) for the white OLEDs with the excellent color rendering index values of more than 80 reported.

Automated summary

A new hybrid local and charge transfer (HLCT) molecule 2TPA-PPI has been developed for high-performance OLEDs. 2TPA-PPI functions as both an efficient emitter and a multi-functional emitting host matrix for phosphorescent OLEDs. By adopting the HLCT/phosphor hybrid strategy, high-efficiency candle light-style OLEDs and quasi-white OLEDs with excellent performance have been achieved.