TY - JOUR
T1 - Enhancing Spin-Orbit Coupling by Introducing a Lone Pair Electron with p Orbital Character in a Thermally Activated Delayed Fluorescence Emitter
T2 - Photophysics and Devices
AU - Chen, Zhanxiang
AU - Ni, Fan
AU - Wu, Zhongbin
AU - Hou, Yuchen
AU - Zhong, Cheng
AU - Huang, Manli
AU - Xie, Guohua
AU - Ma, Dongge
AU - Yang, Chuluo
N1 - Publisher Copyright:
© Copyright 2019 American Chemical Society.
PY - 2019/6/6
Y1 - 2019/6/6
N2 - Reverse intersystem crossing (RISC) is the rate-limited step for the radiative process of thermally activated delayed fluorescence (TADF) materials, which is important to achieve ideal photoluminescence and electroluminescence efficiency. Herein, we propose a new strategy of introducing a lone pair (n) electron with p orbital character to enhance spin-orbit coupling (SOC) for promoting the RISC process. A proof-of-concept TADF molecule with p orbital lone pairs, namely, MoCz-PCN, was developed, and three counterparts without any p lone pairs, namely, DMAc-PCN, DPAc-PCN, and SpiroAc-PCN, were constructed for comparison. The experimental data revealed that MoCz-PCN exhibits a ca. 1.9 times higher RISC rate than the counterparts, which can be ascribed to enhanced SOC. Moreover, a significant increase in external quantum efficiency is observed in the MoCz-PCN-based OLED device. These findings provide a feasible strategy to develop highly efficient TADF emitters by introducing a lone pair (n) electron with p orbital character.
AB - Reverse intersystem crossing (RISC) is the rate-limited step for the radiative process of thermally activated delayed fluorescence (TADF) materials, which is important to achieve ideal photoluminescence and electroluminescence efficiency. Herein, we propose a new strategy of introducing a lone pair (n) electron with p orbital character to enhance spin-orbit coupling (SOC) for promoting the RISC process. A proof-of-concept TADF molecule with p orbital lone pairs, namely, MoCz-PCN, was developed, and three counterparts without any p lone pairs, namely, DMAc-PCN, DPAc-PCN, and SpiroAc-PCN, were constructed for comparison. The experimental data revealed that MoCz-PCN exhibits a ca. 1.9 times higher RISC rate than the counterparts, which can be ascribed to enhanced SOC. Moreover, a significant increase in external quantum efficiency is observed in the MoCz-PCN-based OLED device. These findings provide a feasible strategy to develop highly efficient TADF emitters by introducing a lone pair (n) electron with p orbital character.
UR - http://www.scopus.com/inward/record.url?scp=85066911453&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.9b00937
DO - 10.1021/acs.jpclett.9b00937
M3 - 文章
C2 - 31055932
AN - SCOPUS:85066911453
SN - 1948-7185
VL - 10
SP - 2669
EP - 2675
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 11
ER -