TY - JOUR
T1 - A universal solution-processable bipolar host based on triphenylamine and pyridine for efficient phosphorescent and thermally activated delayed fluorescence OLEDs
AU - Li, Nengquan
AU - Fang, Yayun
AU - Li, Le
AU - Zhao, Huiru
AU - Quan, Yiwu
AU - Ye, Shanghui
AU - Fan, Quli
AU - Huang, Wei
N1 - Publisher Copyright:
© 2018
PY - 2018/7
Y1 - 2018/7
N2 - Host materials play an important role in the development of phosphorescent and thermally activated delayed fluorescence (TADF) organic light emitting diodes (OLEDs). Herein, a universal bipolar host material TPA-(PyF)3 based on triphenylamine and pyridine was designed and synthesized through a simple Friedel-Crafts reaction with a high yield of 83.5%. TPA-(PyF)3 possesses a high triplet energy level of 2.83 eV, excellent thermal and morphological stability, and good solution processability. Using TPA-(PyF)3 as a host material, solution-processed OLEDs with a simple single emitting layer were fabricated. Blue phosphorescent OLEDs based on bis((3,5-difluorophenyl)-pyridine) iridium picolinate (FIrpic) show a maximum current efficiency of 18.5 cd A−1 and a maximum brightness of 13,838 cd m−2, with a low current efficiency roll-off of 9.7% at the practical brightness of 100–1000 cd m−2. Green TADF OLEDs using TPA-(PyF)3 as the host and 2,4,5,6-tetrakis(carbazol-9-yl)-1,3-dicyano-benzene (4CzIPN) as the emitter with the same structure of the phosphorescent OLEDs exhibit a maximum current efficiency of 12.7 cd A−1, compared with 10.2 cd A−1 of the control device based on the common host material of 2,6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy). This study demonstrates the effective utilization of TPA-(PyF)3 as a universal bipolar host for both phosphorescent and TADF OLEDs.
AB - Host materials play an important role in the development of phosphorescent and thermally activated delayed fluorescence (TADF) organic light emitting diodes (OLEDs). Herein, a universal bipolar host material TPA-(PyF)3 based on triphenylamine and pyridine was designed and synthesized through a simple Friedel-Crafts reaction with a high yield of 83.5%. TPA-(PyF)3 possesses a high triplet energy level of 2.83 eV, excellent thermal and morphological stability, and good solution processability. Using TPA-(PyF)3 as a host material, solution-processed OLEDs with a simple single emitting layer were fabricated. Blue phosphorescent OLEDs based on bis((3,5-difluorophenyl)-pyridine) iridium picolinate (FIrpic) show a maximum current efficiency of 18.5 cd A−1 and a maximum brightness of 13,838 cd m−2, with a low current efficiency roll-off of 9.7% at the practical brightness of 100–1000 cd m−2. Green TADF OLEDs using TPA-(PyF)3 as the host and 2,4,5,6-tetrakis(carbazol-9-yl)-1,3-dicyano-benzene (4CzIPN) as the emitter with the same structure of the phosphorescent OLEDs exhibit a maximum current efficiency of 12.7 cd A−1, compared with 10.2 cd A−1 of the control device based on the common host material of 2,6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy). This study demonstrates the effective utilization of TPA-(PyF)3 as a universal bipolar host for both phosphorescent and TADF OLEDs.
KW - Bipolar host
KW - OLEDs
KW - Phosphorescence
KW - Solution process
KW - Thermally activated delayed fluorescence
UR - http://www.scopus.com/inward/record.url?scp=85044973791&partnerID=8YFLogxK
U2 - 10.1016/j.jlumin.2018.03.003
DO - 10.1016/j.jlumin.2018.03.003
M3 - 文章
AN - SCOPUS:85044973791
SN - 0022-2313
VL - 199
SP - 465
EP - 474
JO - Journal of Luminescence
JF - Journal of Luminescence
ER -