Cationic Iridium(Ⅲ) Complex Doped in SiO2 Micropowder: Preparation and Application in Light-emitting Diodes

doi:10.15541/jim20150179

Abstract

Abstract:

A silica sol was prepared from tetraethyl orthosilicate by hydrolysis method, then 15wt% cationic iridium(III) complex [Ir(ppy)₂(o-phen)][PF₆] (ppy: 2-phenylpyridine, o-phen: 1-Ethyl-2-(4-(5-(4-tert-butylphenyl)-1, 3, 4-oxadiazol- 2-yl)phenyl)-1H-imidazo[4, 5-f][1, 10]phenanthroline) was doped after the sol being aged for 1 d. The sol was turned into xerogel after it was heated at 45 ℃ for 3 d and kept at room temperature for 10 d, then the yellow luminescent micropowder was obtained after the silica xerogel being grounded and dried at 150 ℃ for 8 h. The luminescent micropowder was blended in epoxy resin at concentrations of 6.0wt%, 9.0wt%, 12.0wt%, 15.0wt%, 18.0wt% and 21.0wt%, and the resultant mixtures were coated on 395 nm-emitting InGaN chips as the down-conversion luminescent materials in light-emitting diodes (LEDs). The LED prepared from poxy resin blended with 12wt% cationic iridium(Ⅲ) complex doped SiO₂ micropowder exhibited the best luminescent performances, with the maximum efficiency of 51.9 lm/W at 40.0 mA forward current and 5 V reverse voltage, the corresponding CIE color coordinate was (0.42, 0.42).

Key words: cationic iridium(III) complex, light-emitting diode, down-conversion luminescent materials, Sol-Gel

CLC Number:

O614

MENG Guo-Yun, CHEN Ze-Yu, LIU Yong, WEI Li-Ying, WANG Zheng-Liang, TANG Huai-Jun. Cationic Iridium(Ⅲ) Complex Doped in SiO₂ Micropowder: Preparation and Application in Light-emitting Diodes[J]. Journal of Inorganic Materials, 2015, 30(11): 1195-1200.

Figures/Tables 7

Fig. 1 Chemical structural formula of the cationic iridium(III) complex

Fig. 2 (a) Cationic iridium(III) complex doped in SiO2 xerogel and (b) in SiO2 micropowder under UV light, and (c, d) SEM images of cationic iridium(III) complex doped in SiO2 micropowder

Fig. 3 TG and DTA curves of the cationic iridium(III) complex doped in SiO2 micropowder

Fig. 4 Normalized excitation (Ex) and emission (Em) spectra of the cationic iridium (III) complex in CH2Cl2 solution (1.0×10-5 mol/L), doped in SiO2 micropowder and pure cationic iridium (III) complex powder λEx = 395 nm, λEm = 580 nm

Fig. 5 Normalized emission spectra of the LEDs prepared from epoxy resin blended with different concentrations of cationic iridium(Ⅲ) complex doped SiO2 micropowder at 20 mA forward current and 5 V reverse voltage

Table 1 Performances of LEDs prepared from iridium(Ⅲ) complex doped SiO2 micropowder with different blending concentrations

Blending concentration/wt%	Forward current/mA	Luminous flux/lm	η_{p, max}/(lm·W^-1)	λ_max/nm	CIE/(x, y)
6.0	20.0	0.57	8.2	576	(0.43, 0.45)
9.0	20.0	0.84	12.0	577	(0.44, 0.46)
12.0	20.0	1.93	32.2	577	(0.47, 0.49)
12.0	40.0	7.26	51.9	579	(0.42, 0.42)
12.0	60.0	4.97	23.6	582	(0.39, 0.37)
15.0	20.0	0.75	10.8	578	(0.48, 0.49)
18.0	20.0	0.73	10.4	578	(0.49, 0.49)
21.0	20.0	0.59	8.4	578	(0.48, 0.49)

Fig. 6 Normalized emission spectra at different forward current of the LED prepared from epoxy resin blended with 12wt% cationic iridium(Ⅲ) complex doped SiO2 micropowder (at 5 V reverse voltage)

References 33

[1]	TSAO J Y, CRAWFORD M H, COLTRIN M E, et al.Toward smart and ultra-efficient solid-state lighting.Advanced Optical Materials, 2014, 2(9): 809-836.
[2]	BERGH A A.Blue laser diode (LD) and light emitting diode (LED) applications.Physica Status Solidi (A), 2004, 201(12): 2740-2754.
[3]	JIA H, GUO L, WANG W, et al.Recent progress in GaN-based light-emitting diodes.Advanced Materials, 2009, 21(45): 4641-4646.
[4]	KRAMES M R, SHCHEKIN O B, MUELLER-MACH R, et al.Status and future of high-power light-emitting diodes for solid- state lighting.Journal of Display Technology, 2007, 3(2): 160-175.
[5]	LONG X, HE J, ZHOU J, et al.A review on light-emitting diode based automotive headlamps.Renewable and Sustainable Energy Reviews, 2015, 41: 29-41.
[6]	YE S, XIAO F, PAN Y X, et al.Phosphors in phosphor-converted white light-emitting diodes: recent advances in materials, techniques and properties.Materials Science and Engineering R, 2010, 71(1): 1-34.
[7]	ZHANG S C, RUAN Y F, JIA G Z, et al.Study of blue-emitting properties of Ce3+ doped YVO4 under ultraviolet excitation.Journal of Inorganic Materials, 2014, 29(10): 1067-1072.
[8]	MACKA M, PIASECKI T, DASGUPTA P K.Light-emitting diodes for analytical chemistry.Annual Review of Analytical Chemistry, 2014, 7: 183-207.
[9]	DEMIR H V, NIZAMOGLU S, ERDEM T, et al.Quantum dot integrated LEDs using photonic and excitonic color conversion.Nano Today, 2011, 6(6): 632-647.
[10]	HE P, WANG H, LIU S, et al.Effect of different alkyl groups at the N-position on the luminescence of carbazole-based β-diketonate europium (III) complexes. Journal of Physical Chemistry A, 2009, 113(46): 12885-12890.
[11]	WANG H, HE P, LIU S, et al.New multinuclear europium (III) complexes as phosphors applied in fabrication of near UV-based light-emitting diodes.Inorganic Chemistry Communications, 2010, 13(1): 145-148.
[12]	SHAO G, ZHANG N, LIN D, et al.A new europium (III)-β- diketonate complex based on diphenylethyne as red phosphors applied in LED.Journal of Luminescence, 2013, 138: 195-200.
[13]	LUO Y, YAN Q, ZHANG Z, et al.White LED based on poly(N-vinylcarbazole) and lanthanide complexes ternary co-doping system.Journal of Photochemistry and Photobiology A: Chemistry, 2009, 206(1): 102-108.
[14]	YAN H, WANG H, HE P, et al.An efficient bonding-type Eu-containing copolymer as red phosphor applied in LED.Inorganic Chemistry Communications, 2011, 14(6): 1065-1068.
[15]	JIN J Y, KIM Y M, LEE S H, et al.Synthesis of an acrylic copolymer bearing fluorescent dye pendants and characterization as a luminescence conversion material in fabrication of a luminescence conversion light-emitting diode.Synthetic Metals, 2009, 159(17/18): 1804-1808.
[16]	JIN J Y, KIM H G, HONG C H, et al.White light emission from a blue LED, combined with a sodium salt of fluorescein dye.Synthetic Metals, 2007, 157(2): 138-141.
[17]	JIN J Y, LEE H Y, LEE S H, et al.InGaN/bivalent fluorescein salt luminescence conversion light-emitting diode: stability and photochemical reaction.Journal of Luminescence, 2007, 127(2): 665-670.
[18]	ZHOU L, LIU S, ZHAO Q, et al.Light-emitting electrochemical cells based on ionic iridium (III) complexes.Progress in Chemistry, 2011, 23(9): 1871-1882.
[19]	COSTA R D, ORTÍ E, BOLINK H J, et al.Luminescent ionic transition-metal complexes for light-emitting electrochemical cells. Angewandte Chemie International Edition, 2012, 51(33): 8178-8211.
[20]	SU H C, CHEN H F, FANG F C, et al.Solid-state white light-emitting electrochemical cells using iridium-based cationic transition metal complexes.Journal of the American Chemical Society, 2008, 130(11): 3413-3419.
[21]	TANG H, LI Y, CHEN Q, et al.Efficient yellow-green light-emitting cationic iridium complexes based on 1, 10- phenanthroline derivatives containing oxadiazole-triphenylamine unit.Dyes and Pigments, 2014, 100: 79-86.
[22]	ZHANG F, DUAN L, QIAO J, et al.Solution-processed blue-green organic light-emitting diodes based on cationic iridium complexes with 1-pyridyl-3-methylimidazolin-2-ylidene-C, C2′ as the ancillary ligand.Organic Electronics, 2012, 13(7): 1277-1288.
[23]	FERNÁNDEZ-HERNÁNDEZ J M, YANG C-H, BELTRÁN J I, et al. Control of the mutual arrangement of cyclometalated ligands in cationic iridium (III) complexes. Synthesis, spectroscopy, and electroluminescence of the different isomers.Journal of the American Chemical Society, 2011, 133(27): 10543-10558.
[24]	TANG H, LI Y, ZHAO B, et al.Two novel orange cationic iridium (III) complexes with multifunctional ancillary ligands used for polymer light-emitting diodes.Organic Electronics, 2012, 13(12): 3211-3219.
[25]	LIU X M, LIU S J, YANG H R, et al.“Turn-on” phosphorescent nanoprobes for sensing homocysteine and cysteine.Chinese Journal of Inorganic Chemistry, 2012, 28(11): 2271-2279.
[26]	LIU X, XI N, LIU S, et al.Highly selective phosphorescent nanoprobes for sensing and bioimaging of homocysteine and cysteine.Journal of Materials Chemistry, 2012, 22(16): 7894-7901.
[27]	WANG S P, LIU C G, ZHANG J J, et al.Thermal stability and fluorescence properties of 1, 10-phenanthroline- tris(o-methylbenzoate) europium (or terbium) complexes in SiO2 gel glasses.Chinese Rare Earths, 2002, 23(4): 9-12.
[28]	DONG W T, ZHU C S.Spectral properties of dye TMQ doped silica film.Acta Optica Sinica, 2000, 20(7): 1000-1003.
[29]	XU L H, QIANG Y H, JIANG L.Photoluminescent properties of CdS quantum dots doped in silica xerogel.Chinese Journal of Luminescence, 2011, 32(3): 227-231.
[30]	WANG H, KANG J, LIU H, et al.Preparation of organically functionalized silica gel as adsorbent for copper ion adsorption.Journal of Environmental Sciences, 2009, 21(11): 1473-1479.
[31]	HE F, HE X, LI Y. Effect of heat treatment on texture and structure of silica xerogels. Journal of Materials Engineering, 2006(z1): 338-344.
[32]	WEI H B, BIAN M Y, LIU Z W, et al.Blue light excited bimetallic Ir(III)-Eu(III) complex using 4-carboxyl-2, 2'-bipyridine as bridge-linking ligand.Scientia Sinica Chemica, 2012, 42(9): 1364-1371.
[33]	ZHANG J Y, CAI L E, ZHANG B P, et al. Efficient hole transport in asymmetric coupled InGaN multiple quantum wells. Applied Physics Letters, 2009, 95(16): 161110-1-3.

Cationic Iridium(Ⅲ) Complex Doped in SiO₂ Micropowder: Preparation and Application in Light-emitting Diodes

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