Ter(9,9-diarylfluorene)s: Highly efficient blue emitter with promising electrochemical and thermal stability
Journal
Journal of the American Chemical Society
Journal Volume
124
Journal Issue
39
Pages
11576-11577
Date Issued
2002
Author(s)
Abstract
Novel ter(9,9-diarylfluorene)s were synthesized by a Suzuki-coupling reaction of 2-bromofluorene (1) and 2,7-fluorenediboronic ester derivatives (3) with high isolated yields (63-86%). The X-ray structure analysis of ter(9,9′-spirobifluorene) (4aa) revealed that the conjugated chromophore adopts a helical conformation. This conformation effectively releases the steric interaction between the fluorene moieties and prevents inter-chromophore interactions. The introduction of aryl groups at the C9 position of fluorene was highly beneficial to the thermal and morphological stability of these oligomers. These terfluorenes exhibit intense blue fluorescence with excellent quantum yields both in solution (∼100%) and in solid state (66-90%), and possess interesting reversible redox properties. Highly efficient blue light-emitting OLED devices were fabricated using 4aa and 4cc as emitters as well as hole transporters. The devices exhibit low turn-on voltage (∼3 V) and high EL external quantum efficiency (2.5-3%). Copyright © 2002 American Chemical Society.
SDGs
Other Subjects
fluorene derivative; polycyclic aromatic hydrocarbon derivative; article; chemical analysis; chemical reaction; electrochemistry; thermostability
Type
journal article