TY - JOUR
T1 - New Concept for HLCT Emitter
T2 - Acceptor Molecule in Exciplex System for Highly Efficient and Extremely Low-Efficiency Roll-Off Solution-Processed OLED
AU - Yin, Yixiao
AU - Wu, Yinyan
AU - He, Binghong
AU - Xia, Zekun
AU - Zhu, Weiguo
AU - Lee, Jun Yeob
AU - Wang, Yafei
N1 - Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/10/7
Y1 - 2024/10/7
N2 - The use of hybridized local and charge-transfer (HLCT) emitters as acceptor or donor molecules in exciplex systems is still a novel concept even though HLCT molecules can harvest both singlet and triplet excitons. Herein, two HLCT emitters, 2-tBuspoCz-2pTrz and 2-tBuspoCz-Me3pTrz, are prepared as acceptors of exciplexes with thermally activated delayed fluorescence (TADF) properties. The exciplex TADF systems constructed by mixing HLCT and TAPC molecules have a minute energy gap between singlet and triplet excited states and unity emission efficiency. Using the exciplex as an emitter, solution-processed devices achieve maximum external quantum efficiency (EQEmax) of 16.6%. Impressively, solution-processed devices with the fabricated exciplexes as hosts exhibit extremely low turn-on voltages and a promising EQEmax of >20%, which is concomitant with an extremely low-efficiency roll-off of 0.5% at 1,000 cd m-2. This study explores the potential of HLCT emitters as acceptors of exciplexes and guides the design of efficient exciplex systems.
AB - The use of hybridized local and charge-transfer (HLCT) emitters as acceptor or donor molecules in exciplex systems is still a novel concept even though HLCT molecules can harvest both singlet and triplet excitons. Herein, two HLCT emitters, 2-tBuspoCz-2pTrz and 2-tBuspoCz-Me3pTrz, are prepared as acceptors of exciplexes with thermally activated delayed fluorescence (TADF) properties. The exciplex TADF systems constructed by mixing HLCT and TAPC molecules have a minute energy gap between singlet and triplet excited states and unity emission efficiency. Using the exciplex as an emitter, solution-processed devices achieve maximum external quantum efficiency (EQEmax) of 16.6%. Impressively, solution-processed devices with the fabricated exciplexes as hosts exhibit extremely low turn-on voltages and a promising EQEmax of >20%, which is concomitant with an extremely low-efficiency roll-off of 0.5% at 1,000 cd m-2. This study explores the potential of HLCT emitters as acceptors of exciplexes and guides the design of efficient exciplex systems.
UR - https://www.scopus.com/pages/publications/85205915662
U2 - 10.1021/acsmaterialslett.4c01643
DO - 10.1021/acsmaterialslett.4c01643
M3 - Article
AN - SCOPUS:85205915662
SN - 2639-4979
VL - 6
SP - 4738
EP - 4747
JO - ACS Materials Letters
JF - ACS Materials Letters
IS - 10
ER -