Pyrene-Based Blue AIEgen: Enhanced Hole Mobility and Good EL Performance in Solution-Processed OLEDs.

Jie Yang,Jianwen Qin,Qian Peng,Guohua Xie,Zichun Ren,Zhen Li

doi:10.3390/molecules22122144

Abstract

Organic luminogens with strong solid-state emission have attracted much attention for their widely practical applications. However, the traditional organic luminogens with planar conformations often suffer from the notorious aggregation-caused quenching (ACQ) effect in solid state for the π–π stacking. Here, a highly efficient blue emitter TPE-4Py with an aggregation-induced emission (AIE) effect is achieved by combining twisted tetraphenylethene (TPE) core and planar pyrene peripheries. When the emitter was spin-coated in non-doped OLEDs with or without a hole-transporting layer, comparable EL performance was achieved, showing the bifunctional property as both an emitter and a hole-transporting layer. Furthermore, its EL efficiency was promoted in doped OLED, even at a high doping concentration (50%), because of its novel AIE effect, with a current efficiency up to 4.9 cd/A at 484 nm.

Highlights

Organic light-emitting diodes (OLEDs) have drawn increasing interest for their wide applications in full-color display and white light illumination [1,2]
When the emitter was spin-coated in non-doped OLEDs with or without a hole-transporting layer, comparable EL performance was achieved
Its thermal properties were investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC)

Summary

Introduction

Organic light-emitting diodes (OLEDs) have drawn increasing interest for their wide applications in full-color display and white light illumination [1,2]. Since first synthesized by Weitzenböck in 1913, pyrene and its derivatives have attracted particular attention in the research of blue emissive materials for their high quantum efficiency and good hole-transporting ability [7,8]. Another strategy was utilized, with an AIE building block acting as a core and pyrene as a peripheral group, where a series of efficient blue materials was developed with enhanced hole-transporting ability, achieving a good interaction between pyrene peripheries (Chart S2) [13].

Results

Conclusion