A Twisting Donor-Acceptor Molecule with an Intercrossed Excited State for Highly Efficient, Deep-Blue Electroluminescence

doi:10.1002/adfm.201200116

CORC > 化学研究所 > 中国科学院化学研究所

	A Twisting Donor-Acceptor Molecule with an Intercrossed Excited State for Highly Efficient, Deep-Blue Electroluminescence
	Li, Weijun 1; Liu, Dandan 1; Shen, Fangzhong 1; Ma, Dongge 2; Wang, Zhiming 1; Feng, Tao 1; Xu, Yuanxiang 1; Yang, Bing 1; Ma, Yuguang 1
刊名	ADVANCED FUNCTIONAL MATERIALS
	2012-07-10
卷号	22 期号:13 页码:2797-2803
关键词	Charge-transfer (Ct) States Intercrossing High Efficiency Nondoped Oleds
ISSN号	1616-301X
DOI	10.1002/adfm.201200116
英文摘要	In an organic electroluminescent (EL) device, the recombination of injected holes and electrons produces what appears to be an ion-pair or charge-transfer (CT) exciton, and this CT exciton decays to produce one photon directly, or relaxes to a low-lying local exciton (LE). Thus the full utilization of both the energy of the CT exciton and the LE should be a pathway for obtaining high-efficiency EL. Here, a twisting donor-acceptor (D-A) triphenylamine-imidazol molecule, TPA-PPI, is reported: its synthesis, photophysics, and EL performance. Prepared by a manageable, one-pot cyclizing reaction, TPA-PPI exhibits deep-blue emission with high quantum yields (90%) both in solution and in the solid state. Fluorescent solvatochromic experiments for TPA-PPI solutions show a red-shift of 57 nm (3032 cm-1) from low-polarity hexane (406 nm) to high-polarity acetonitrile (463 nm), accompanied by the gradual disappearance of the vibrational band in the spectra with increased solvent polarity. The photophysical investigation and DFT analysis suggest an intercrossed CT and LE excited state of the TPA-PPI, originating from its twisting D-A configuration. This is a rare instance that a CT-state material shows highly efficient deep-blue emission. EL characterization demonstrates that, as a deep-blue emitter with CIE coordinates of (0.15, 0.11), the performance of a TPA-PPI-based device is rather excellent, displaying a maximum current efficiency of >5.0 cd A-1, and a maximum external quantum efficiency of >5.0%, corresponding to a maximum internal quantum efficiency of >25%. The effective utilization of the excitation energy arising from materials with intercrossed-excited-state (LE and CT) characters is thought to be beneficial for the improved efficiency of EL devices.
语种	英语
出版者	WILEY-V C H VERLAG GMBH
WOS记录号	WOS:000305945000018
内容类型	期刊论文
源URL	[http://ir.iccas.ac.cn/handle/121111/48937]
专题	中国科学院化学研究所
通讯作者	Li, Weijun
作者单位	1.Jilin Univ, State Key Lab Supramol Struct & Mat, Changchun 130012, Peoples R China 2.Chinese Acad Sci, Changchun Inst Appl Chem, State Key Lab Polymer Phys & Chem, Changchun 130022, Peoples R China
推荐引用方式 GB/T 7714	Li, Weijun,Liu, Dandan,Shen, Fangzhong,et al. A Twisting Donor-Acceptor Molecule with an Intercrossed Excited State for Highly Efficient, Deep-Blue Electroluminescence[J]. ADVANCED FUNCTIONAL MATERIALS,2012,22(13):2797-2803.
APA	Li, Weijun.,Liu, Dandan.,Shen, Fangzhong.,Ma, Dongge.,Wang, Zhiming.,...&Ma, Yuguang.(2012).A Twisting Donor-Acceptor Molecule with an Intercrossed Excited State for Highly Efficient, Deep-Blue Electroluminescence.ADVANCED FUNCTIONAL MATERIALS,22(13),2797-2803.
MLA	Li, Weijun,et al."A Twisting Donor-Acceptor Molecule with an Intercrossed Excited State for Highly Efficient, Deep-Blue Electroluminescence".ADVANCED FUNCTIONAL MATERIALS 22.13(2012):2797-2803.