具有快上转化速率的窄光谱蓝光多重共振发光材料
Blue multiple resonance emitters exhibiting fast spin flip
田杨 1苏蓉川 2刘俊杰 1雷搏文 1刘旻昊 1宾正杨1
作者信息
- 1. College of Chemistry,Sichuan University,Chengdu 610064,China
- 2. Department of Pharmacology,North Sichuan Medical University,Nanchong 637100,China
- 折叠
摘要
如何提高蓝光多重共振发光材料的反隙间窜跃速率(kRISC),并维持较快的辐射跃迁速率(kR)是促进其进一步发展和应用的关键.本论文报道了一种简单且高效的"空间限制的受体-供体-受体(SCADA)"策略,旨在加速蓝色多重共振发光分子的上转化过程.在多重共振中心骨架的最高占据轨道(HOMO)分布位点引入两个氰基苯受体,并在最低位占据轨道(LUMO)引入一个叔丁基咔唑给体,使发射波长蓝移的同时,减小发射的半峰宽(FWHM).此外,供体单元和受体单元呈现近距离的面对面取向,产生分子内给受体相互作用,进而增强自旋轨道耦合,加速反隙间窜跃过程,基于"SCADA"策略,本文成功开发出蓝光多重共振发光分子2DCNCz-BN,其FWHM仅为19 nm,并同时具有较快的kRISC(1.8 × 106s-1)和kR(2.0 × 108 s-1).以2DCNCz-BN为发光分子的OLED器件,最大外量子效率(EQEmax)为30.2％,并展现出较低的效率滚降,在1000 cdm-2的亮度下,EQE可以维持22.3％.
Abstract
The ongoing pursuit of developing high-per-formance narrowband blue multiple resonance(MR)emitters that feature a fast reverse intersystem crossing(RISC)rate(kRISC)presents a significant challenge.To address this,we introduce an efficient approach:The"space-confined ac-ceptor-donor-acceptor(SCADA)"strategy,aiming at accel-erating the RISC process in the development of blue MR emitters.By integrating two cyanobenzene acceptors and one carbazole donor onto the MR skeleton results,we achieve a blue-shifted emission with a reduced full width at half max-imum(FWHM).This structural arrangement encourages the donor and acceptor units to align face-to-face at close proxi-mity,which leads to intramolecular noncovalent interactions and enhances spin-orbit coupling.Consequently,the"SCA-DA"strategy gives rise to a superior blue MR emitter char-acterized by a small FWHM of 19 nm,a fast kRISC of 1.8 × 106 s-1,as well as a fast radiative decay rate(kR)of 2.0 × 108 s-1.These attributes facilitate the assembly of high-performance narrowband blue organic light-emitting diodes with a high maximum external quantum efficiency of 30.2％and low ef-ficiency roll-off.
关键词
multiple resonance emitter/boron-nitrogen em-bedded framework/fast radiative decay rate/fast reverse inter-system crossing rate/narrowband blue emissionKey words
multiple resonance emitter/boron-nitrogen em-bedded framework/fast radiative decay rate/fast reverse inter-system crossing rate/narrowband blue emission引用本文复制引用
基金项目
National Natural Science Foundation of China(22275127)
出版年
2024
NETL
NSTL
万方数据