Title
High Green Brightness Circularly Polarized Electroluminescence Regulated by Rigid Chiral D-A Type Emitters
Author
Yu Zhang, Xueyan Zhang, Haiping Zhang, Yuping Xiao, Yiwu Quan, Shanghui Ye, Yixiang Cheng
Year
2019
Journal
The Journal of Physical Chemistry C
Abstract
In this paper, a pair of rigid chiral D-A type enantiomers (S-/R-2) incorporating the pyrene moiety as the donor and 1,8-naphthalimide as the acceptor was chosen as circularly polarized electroluminescence (CP-EL) emitters. This kind of chiral emitter exhibits good thermal stability (Td = 389 °C, Tg = 112 °C), high fluorescence quantum yields (46.4/42.4%), and CPL-active materials (glum = +1.46 × 10–3/–1.40 × 10–3 for S-/R-2) in the solid state. The nondoped OLEDs with the structure of ITO/PEDOT:PSS (25 nm)/S-2 or R-2 (35 nm)/TPBi (35 nm)/Ca (10 nm)/Ag (100 nm) show turn-on voltages of 4.4 and 4.2 V, maximum luminance values of 19575 and 18411 cd m–2, maximum current efficiencies of 2.8 and 3.2 cd A–1, and high green brightness CP-EL signals with gEL values of +2.15 × 10–3 and −2.23 × 10–3 for S-2 and R-2, respectively.
Instrument
J-810, CPL-300
Keywords
Circular dichroism, Circularly polarized luminescence, Stereochemistry, Chemical stability, Solid state, Materials