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Indexed by:期刊论文

Date of Publication:2017-12-01

Journal:DYES AND PIGMENTS

Included Journals:Scopus、SCIE、EI

Volume:147

Page Number:465-475

ISSN No.:0143-7208

Key Words:AIEE; Triarylcyclopentadiene derivatives; Crystal structures; Fluorescence; OLEDs

Abstract:Five highly efficient blue-emitting triarylcyclopentadiene derivatives 1-5 were designed and synthesized by introducing phenyl, methoxyphenyl, methoxybiphenyl and methoxynaphthyl groups to cyclopentadiene backbone, respectively. These compounds possess good thermal stability with decomposition temperatures of 264-340 degrees C and exhibit intense blue fluorescence with maximum emission peaked at 457-470 nm. All compounds emit weak fluorescence in solution, but they become strong emitters in the aggregated state indicating typical aggregation-induced emission enhancement (AIEE) properties. AIEE behaviour was further confirmed by fluorescent changes depended on temperature and solution viscosity as well as time-resolved fluorescence lifetime measurements. Unexpected substituent effect on aggregation structures and fluorescent properties of 1-5 was also observed. Single-crystal structure analysis revealed that highly twisted conformations and bulky substituents on cyclopentadiene core could dramatically suppress the intermolecular pi-pi interactions leading to intense blue emission of these compounds in aggregates. Furthermore, the non-doped and doped organic light-emitting diodes (OLEDs) using compounds 2 and 5 as the emitting layers have been fabricated, respectively. A non-doped OLED with compound 5 displays good electroluminescent performance with a light-blue emission and a maximum luminance of 3886 cd/m(2). (C) 2017 Elsevier Ltd. All rights reserved.