Asymmetrical fluorene[2,3-b]benzo[d]thiophene derivatives: synthesis, solid-state structures, and application in solution-processable organic light-emitting diodes.
A series of novel asymmetrical fused compounds containing the backbone of fluorene[2,3-b]benzo[d]thiophene (FBT) were effectively synthesized and fully characterized. Single-crystal X-ray studies demonstrated that the length of the substituent side chains greatly affects the solid-state packing of the obtained fused compounds. DFT, photophysical, and electrochemical studies all showed that the FBTs have large band gaps, low-lying HOMO energy levels, and therefore good stability toward oxidation. Moreover, the substituents strongly influence the fluorescence properties of the resulting FBT derivatives. The di-n-hexyl compound exhibits intense fluorescence in solution with the highest quantum yield of up to 91 %. Solution-processed green phosphorescent organic light-emitting diodes with the di-n-butyl derivative as the host material exhibited a maximum brightness of 14,185 cd m(-2) and a luminescence efficiency of 12 cd A(-1).
Du
Chunyan
C
Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Ye
Shanghui
S
Chen
Jianming
J
Guo
Yunlong
Y
Liu
Yunqi
Y
Lu
Kun
K
Liu
Ying
Y
Qi
Ting
T
Gao
Xike
X
Shuai
Zhigang
Z
Yu
Gui
G