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Progress in long wavelength emission in fluorene-based electroluminescent blue materials

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Abstract

On account of the advantages of organic electroluminescent materials compared with their inorganic counterparts, the development of organic electroluminescent materials is one of the hot areas of the optoelectronic materials. Fluorene and its derivatives, which have an aromatic biphenyl structure with a wide energy gap in the backbones and high luminescent efficiency, have drawn much attention of material chemists and device physicists. However, one drawback of fluorene-based electroluminescent blue materials is that there is an occurrence of long wavelength emission after annealing the films in air or after operating organic light-emitting diodes for a long time. To clarify the origin of this long wavelength emission, the scientists at home and abroad have put forward all kinds of correlative explanations. Among the scientists, some thought it was caused by excimer-related species, while some others claimed that it was caused by the fluorenone of photooxdized fluorene. The corresponding solutions to this problem have also been proposed and the problem has been partially resolved in some degree. The present review summarizes and analyzes the progress made on the origin of long wavelength emission in fluorene-based electroluminescent blue materials at home and abroad in the past few years. Some issues to be addressed and hotspots to be further investigated are also presented and discussed.

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Authors and Affiliations

  1. Jiangsu Key Laboratory for Organic Electronics & Information Displays and Institute of Advanced Materials, Nanjing University of Posts & Telecommunications, Nanjing, 210046, China

    HongJi Jiang & Huang Wei

  2. Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou, 310012, China

    Wan JunHua

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Correspondence to Huang Wei.

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Supported by the National Natural Science Foundation of China (Grant Nos: 90406021, 20774043 and 20574012), Natural Science Foundation of Jiangsu College Council (Grant No: KJD150148), and Scientific Research Foundation of Nanjing University of Posts and Telecommunications (Grant No: NY206069)

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Jiang, H., JunHua, W. & Wei, H. Progress in long wavelength emission in fluorene-based electroluminescent blue materials. Sci. China Ser. B-Chem. 51, 497–520 (2008). https://doi.org/10.1007/s11426-008-0053-0

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