基于芘并咪唑的电致发光材料的合成与表征

doi:10.7503/cjcu20170049

摘要/Abstract

摘要：

以芘和咪唑为基本构筑单元, 利用 “一锅法”合成了一系列芘并咪唑衍生物PyPI, PyTPAI, PyCzI和Pyd-CzI. 采用质谱、核磁和元素分析等手段表征了化合物的结构. 通过调节与芘并咪唑相连接的共轭基团的种类、大小和空间构型, 实现对分子热学性质, 分子轨道能级和光电性质的调控. 进一步制备了有机电致发光器件, 得到了较好的器件性能.

关键词: 芘并咪唑, 一锅法, 有机电致发光器件, 量子效率

Abstract:

A series of organic fluorescent materials based on pyrene-imidazole was designed and synthesized by one-pot reactions. The compounds were thoroughly characterized by ¹H NMR and ¹³C NMR spectroscopy, mass spectroscopy and elemental analysis and corresponded well with their expected structures. The conjugation degree, spatial structure, the highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) energy levels are fine-tuned by the various substituents at C1 position of imidazole. They also increase the thermal stabilities of these pyrene-imidazole derivatives. These materials show potential applications in organic light-emitting diodes.

Key words: Pyrene-imidazole, One-pot reaction, Organic light-emitting diode, Quantum efficiency

中图分类号:

O626

TrendMD:

刘豫龙, 路芳, 路萍. 基于芘并咪唑的电致发光材料的合成与表征. 高等学校化学学报, 2017, 38(4): 583.

LIU Yulong, LU Fang, LU Ping. Design, Synthesis and Electroluminescence of Organic Conjugated Compounds Based on Pyrene-imidazole^†. Chem. J. Chinese Universities, 2017, 38(4): 583.

图/表 9

Scheme 1 Synthetic routes of four pyrene-imidazole based materials

Fig.1 Molecular optimized configurations

Fig.2 Molecular electronic orbital distributions

Fig.3 Cyclic voltammogram curves in CH2Cl2(oxidation) and DMF(reduction) measured with 0.1 mol/L (Bu4N)PF6 as supporting electrolyte at a scan rate of 100 mV/s

Fig.4 Normalized absorption(A, C) and emission spectra(B, D) in tetrahydrofuran (A, B) (10-5 mol/L) and in ﬁlm(30 nm)(C, D)

Table 1 Optical and electrochemical properties of the compounds

Compd.	λ_sol/nm		λ_film/nm		$E gap c$ / eV	$E gap d$ / eV	FWHM^e/ nm	(λ_film- λ_sol)^f/ nm	$Φ fl g$ (sol/film)
Compd.	Abs^a	PL^a			$E gap c$ / eV	$E gap d$ / eV	FWHM^e/ nm	Abs^b	PL^b
PyPI	291, 330, 382	384, 405, 430	297, 338, 385	454	3.20^c	3.24^d	80	70	0.75/0.18
PyCzI	291, 340, 385	392, 414, 438	297, 347, 388	433	3.14^c	3.12^d	64	41	0.66/0.52
Pyd-CzI	293, 340, 385	396, 415, 438	296, 347, 388	442	3.13^c	3.00^d	61	27	0.58/0.48
PyTPAI	293, 350, 387	409, 427	298, 355, 389	451, 464	2.88^c	2.73^d	80	24	0.99/0.65

Table 1 Optical and electrochemical properties of the compounds

Compd.	λ_sol/nm		λ_film/nm		$E gap c$ / eV	$E gap d$ / eV	FWHM^e/ nm	(λ_film- λ_sol)^f/ nm	$Φ fl g$ (sol/film)
Compd.	Abs^a	PL^a			$E gap c$ / eV	$E gap d$ / eV	FWHM^e/ nm	Abs^b	PL^b
PyPI	291, 330, 382	384, 405, 430	297, 338, 385	454	3.20^c	3.24^d	80	70	0.75/0.18
PyCzI	291, 340, 385	392, 414, 438	297, 347, 388	433	3.14^c	3.12^d	64	41	0.66/0.52
Pyd-CzI	293, 340, 385	396, 415, 438	296, 347, 388	442	3.13^c	3.00^d	61	27	0.58/0.48
PyTPAI	293, 350, 387	409, 427	298, 355, 389	451, 464	2.88^c	2.73^d	80	24	0.99/0.65

Fig.5 DSC(A) and TGA(B) curves under nitrogen at a heating rate of 10 ℃/min

Table 2 Electroluminescence properties of the devices

Device	CIE^a(x, y)	Voltage^b/V	CE^c/(cd·A^-1)	PE^d/(lm·W^-1)	L^e/(cd·m^-2)	EQE^f(%)
PyPI	(0.160, 0.244)	4.0	1.95	1.24	9615	1.29
PyTPAI	(0.162, 0.168)	3.5	1.66	1.36	4964	1.16
PyCzI	(0.157, 0.166)	3.0	1.91	1.45	8063	1.62
Pyd-CzI	(0.161, 0.194)	3.5	1.97	1.52	7217	1.61

Fig.6 Energy level diagrams of the investigated organic light-emitting diodes(OLED)(A), current density-voltage(J-V) characteristics(B), current efficiency vs. voltage curves(C) and electroluminescence(EL) spectra measured at 7 V(D)

参考文献 21

[1]	Figueira-Duarte T. M., Müllen K., Chem. Rev., 2011, 111, 7260—7314
[2]	Liu Y. L., Shan T., Yao L., Bai Q., Guo Y. C., Li J. Y., Han X., Li W. J., Wang Z. M., Yang B., Lu P., Ma Y. G., Org. Lett., 2015, 17, 6138—6141
[3]	Liu M. F., Chen Y. L., Zhu B., Han Y., Huang W. G., Du C., Bo Z. S., Chinese J. Polym. Sci., 2012, 30, 405—414
[4]	Winnik F. M., Chem. Rev., 1993, 93, 587—614
[5]	Berlman I. B., J. Phys. Chem., 1970, 74, 3085—3093
[6]	Li H. P., Wang P. F., Wu S. K., Chem. J. Chinese Universities, 1999, 20(6), 872—878
	(李华平, 汪鹏飞, 吴世康. 高等学校化学学报, 1999,20(6), 872—878)
[7]	Gao F., Yan Y., Ren B. Y., Tong Z., Chem. J. Chinese Universities, 2000, 21(6), 976—979
	(高峰, 严宇, 任碧野, 童真. 高等学校化学学报, 2000,21(6), 976—979)
[8]	Wu K. C., Ku P. J., Lin C. S., Shi H. T., Wu F. I., Huang M. J., Lin J. J., Chen I. C., Cheng C. H., Adv. Funct. Mater., 2008, 18, 67—75
[9]	Chan K. L., Lim J. P., Yang X. H., Dodabalapur A., Jabbour G. E., Sellinger A., Chem. Commun., 2012, 48, 5106—5108
[10]	Gu J. F., Xie G. H., Zhang L., Chen S. F., Lin Z. Q., Zhang Z. S., Zhao J. F., Xie L. H., Tang C., Zhao Y., Liu S. Y., Huang W., J. Phys. Chem. Lett., 2010, 1, 2849—2853
[11]	Hong Y. N., Lam J. W. Y., Tang B. Z., Chem. Soc. Rev., 2011, 40, 5361—5388
[12]	Zhao Z. J., Chen S. M., Lam J. W. Y., Lu P., Zhong Y. C., Wong K. S., Kwok H. S., Tang B. Z., Chem. Commun., 2010, 46, 2221—2223
[13]	Zhao Z. J., Lu P., Lam J. W. Y., Wang Z. M., Chan C. Y. K., Sung H. H. Y., Williams I. D., Ma Y., Q., Tang B. Z., Chem. Sci., 2011, 2, 672—675
[14]	Li W. J., Gao Z., Wang Z. M., Yang B., Lu P., Ma Y. G., Chem. J. Chinese Universities, 2014, 35(9), 1849—1858
	(李维军, 高瞾, 王志明, 杨兵, 路萍, 马於光. 高等学校化学学报, 2014,35(9), 1849—1858)
[15]	Li W. J., Liu D. D., Shen F. Z., Ma D. G., Wang Z. M., Feng T., Xu Y. X., Yang B., Ma Y. G., Adv. Funct. Mater., 2012, 22, 2797—2803
[16]	Liu H. C., Bai Q., Yao L., Zhang H. Y., Xu H., Zhang S. T., Li W. J., Gao Y., Li J. Y., Lu P., Wang H. Y., Yang B., Ma Y. G., Chem. Sci., 2015, 6, 3797—3804
[17]	Gao Z., Cheng G., Shen F. Z., Zhang S. T., Zhang Y. N., Lu P., Ma Y. G., Laser & Photonics Rev., 2014, 8, L6—L10
[18]	Liu M., Li X. L., Chen D. C., Xie Z. Z., Cai X. Y., Xie G. Z., Liu K. K., Tang J. X., Su S. J., Cao Y., Adv. Funct. Mater., 2015, 25, 5190—5198
[19]	Wang J., Dyers L., Mason R., Amoyaw P., Bu X. R., J. Org. Chem., 2005, 70, 2353—2356
[20]	Hu J., Zhang D., Harris F. W., J. Org. Chem., 2005, 70, 707—708
[21]	Wu J. S., Pisula W., Müllen K., Chem. Rev., 2007, 107, 718—747