This research was supported by “973” (2002CB613401), China, China Postdoctoral Science Foundation and the K. C. Wong Education Foundation, Hong Kong. We thank Prof. S. E. Webber (University of Texas at Austin) for his kind help with the English. Supporting Information is available online from Wiley InterScience or from the author.
A Hole-Transporting Material with Controllable Morphology Containing Binaphthyl and Triphenylamine Chromophores†
Article first published online: 18 MAY 2006
Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 16, Issue 10, pages 1343–1348, July, 2006
How to Cite
He, Q., Lin, H., Weng, Y., Zhang, B., Wang, Z., Lei, G., Wang, L., Qiu, Y. and Bai, F. (2006), A Hole-Transporting Material with Controllable Morphology Containing Binaphthyl and Triphenylamine Chromophores. Adv. Funct. Mater., 16: 1343–1348. doi: 10.1002/adfm.200500541
- Issue published online: 26 JUN 2006
- Article first published online: 18 MAY 2006
- Manuscript Accepted: 12 DEC 2005
- Manuscript Received: 11 AUG 2005
- Charge transfer;
- Hole transport;
- Light-emitting diodes, organic
An organic compound with two triphenylamine moieties linked with binaphthyl at the 3,3′-positions (2,2′-dimethoxyl-3,3′- di(phenyl-4-yl-diphenyl-amine)-[1,1′]-binaphthyl, TPA–BN–TPA) can be synthesized by Suzuki coupling. Amorphous and homogeneous films are obtained by either vacuum deposition or spin-coating from solution in good solvents, while single crystals are grown in an appropriate polar solvent. X-ray crystallography showed that a TPA–BN–TPA crystal is a multichannel structure containing solvent molecules in the channels. The intramolecular charge-transfer state resulting from amino conjugation effects is observed by solvatochromic experiments. The high glass-transition temperature (130 °C) and decomposition temperature (439 °C) of this material, in combination with its reversible oxidation property, make it a promising candidate as a hole-transport material for light-emitting diodes. With TPA–BN–TPA as the hole-transporting layer in an indium tin oxide/TPA–BN–TPA/aluminum tris(8-hydroxyquinoline)/Mg:Ag device, a brightness of about 10 100 cd m–2 at 15.6 V with a maximum efficiency of 3.85 cd A–1 is achieved, which is superior to a device with N,N′-di(1-naphthyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine as the hole-transporting layer under the same conditions. Other devices with TPA–BN–TPA as the blue-light-emitting layer or host for a blue dye emitter are also studied.