Red fluorescent materials based on julolidine/chromene with the bulky tert-butyl and trimethylsilyl substituents for organic light-emitting diodes.
In this work, we designed and synthesized two red emitters 2-(6,8-di-tert-butyl-2-(2-(1,1-dimethyl-7-(trimethylsilyl)-7-((trimethylsilyl)methyl)-1,2,3,5,6,7-hexahydropyrido[3,2,1-ij]quinolin-9-yl)vinyl)-4H-chromen-4-ylidene)malononitrile (Red 1) and 2-(6,8-di-tert-butyl-2-(2-(1,1,7-trimethyl-7-t-butyl)-1,2,3,5,6,7-hexahydropyrido[3,2,1-ij]quinolin-9-yl)vinyl)-4H-chromen-4-ylidene)malononitrile (Red 2). To explore the electro-luminescence properties of these materials, multilayered OLEDs using these materials as dopants in a Alq3 host were fabricated. Particularly, by using Red 1 as a dopant in emitting layer, device 1 showed the luminous and power efficiencies of 0.81 cd/A and 0.43 lm/W at 20 mA/cm2, respectively. The CIE coordinates of this device was (0.65, 0.34) at 7.0 V, which is close to the NTSC standard CIE coordinates of (0.67,0.32) for red emission.
Eun Jae
EJ
Na
Hye Jeong
HJ
Kim
Kum Hee
KH
Lee
Seok Jae
SJ
Lee
Young Kwan
YK
Kim
Seung Soo
SS
Yoon
D001578:Benzopyrans / Q000737:chemistry*; D005453:Fluorescence; D008027:Light; D066244:Proton Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization
D001578:Benzopyrans