【作者】 徐茂梁；

【导师】 李文连； 安忠维；

【作者基本信息】 中国科学院研究生院（长春光学精密机械与物理研究所） ， 凝聚态物理， 2005， 博士

【摘要】 为了提高有机磷光发光器件(PhOLEDs)性能,设计了一系列新型磷光Ir-配合物,合成了2,5-二苯基吡啶,2-苯基噻唑,芳基喹啉(异喹啉),2-苯并噻吩吡啶及其衍生物配体12种(其中9种为新配体)及其环金属铱配合物(cyclometalated iridium complexes)有机磷光材料16种(其中新材料14种)。主要设计思路是修饰配体化合物,大多数配合物具有(C^N)2Ir(acac)通式,其中,acac为乙酰丙酮,(C^N)为环金属化配体(即:2,5-二苯基吡啶(dppy),2,5-二(4-甲氧基苯基)吡啶(dmoppy),2,5-二(4-乙氧基苯基)吡啶(deoppy),2,5-二(4-乙基苯基)吡啶(deppy),2-苯基噻唑(ptz),2-(4-乙基苯基)噻唑(eptz),2-(4-甲氧基苯基)喹啉(mopq),2-(4-联苯基)喹啉(bpq),1-(4-联苯基)异喹啉(bpiq),2-苯并噻吩基-4-甲基吡啶(btmp),2-苯并噻吩基-5-三氟甲基吡啶(btfmp)),同时还培养出了配合物(dppy)2Ir(acac), (bpq)2Ir(acac)及(btmp)2Ir(acac)的单晶,并用X-ray衍射法测定了结构,对其中的配合物(dppy)2Ir(acac)及(btmp)2Ir(acac),运用B3LYP密度泛函理论作了基态电子计算,了解到其HOMO能级由Ir及配体轨道组成,而LUMO能级主要基于环金属化配体。对配合物的吸收、发射、热稳定性及电化学性质作了系统的研究,发现这些配合物发射绿到红色磷光,波长范围为531-648nm,在电化学方面,这些配合物具有源于Ir(Ⅲ)→Ir(Ⅳ)的可逆氧化波,籍由氧化电势可确定其HOMO及LUMO能级。大多数配合物10%重量损失时的温度在300-400oC,适合器件的制作。基于Ir(dmoppy)3的绿色磷光器件,外量子效率为9%,流明效率36cd/A,最大亮度为35000cd/m2。以(btfmp)2Ir(acac)作磷光掺杂剂的红色器件,电流密度0.125 mA/cm2时外量子效率为9.6%,而电流密度为100 mA/cm2时仍然高达3.7%,发射波长为648nm,色坐标为(x=0.69, y=0.29)。以(btfmp)2Ir(acac)作磷光掺杂剂,以PVK-PBD为基质制作的红色聚合物磷光器件,发射峰位648nm,15%掺杂时获得最大外量子效率4.5%,这意味着降低了高浓度下浓度猝灭效应。总之,通过对配体化合物的不同位置及采用不同取代基修饰,获得了一些新型磷光Ir-配合物发光掺杂剂材料,并研制出了高性能OLED器件。更多还原

【Abstract】 In order to increase the performances of phosphorescent OLEDs, in this thesis, a series of phosphorescent iridium complexes were designed and twelve ligands (including nine of new ligands) and sixteen of cyclometalated iridium complexes (including fourteen of new complexes) with 2,5-diphenylpyridine, 2-phenylthiazole, arylquinoline (isoquinoline), and 2-benzo[b]-thiophen-2-yl-pyridine based ligands have been synthesized and characterized to investigate the effect of the simple ligand modification on photophysics, thermostability and electrochemistry. The majority of the complexes have the general structure (C^N)2Ir(acac), where acac is acetylacetone, (C^N)2 is a monoanionic cyclometalating ligand (e.g., 2,5-diphenylpyridyl (dppy), 2,5-di(4-methoxyphenyl)-pyridyl (dmoppy), 2,5-di(4-ethoxyphenyl)pyridyl (deoppy), 2,5-di(4-ethylphenyl)-pyridyl (deppy), 2-phenylthiazole (ptz), 2-(4-ethylphenyl)- thiazole (eptz), 2-(4-methoxyphenyl)quinoline (mopq), 2-(4-biphenyl)quinoline (bpq), 1-(4-biphenyl)isoquinoline (bpiq), 2-benzo[b]thio-phenyl-4-methylpyridine (btmp), and 2-benzo[b]thiophenyl-5-trifluoromethyl- pyridine (btfmp) ). The (dppy)2Ir(acac), (bpq)2Ir(acac), and (btmp)2Ir(acac) have been characterized using X-ray crystallography. Calculation on the electronic ground state of (dppy)2Ir(acac) and (btmp)2Ir(acac) were carried out using B3LYP density functional theory. HOMO levels are a mixture of Ir and ligand orbitals, while the LUMO is predominantly monoanionic cyclometalating ligand based. The absorption, emission, cyclic voltammetry and thermostability of the complexes were systematically investigated. The complexes emit green to red phosphorescence with wavelengths ranging from 531 to 648nm. The iridium complexes exhibit an reversible oxidation wave due to Ir(Ⅲ)→Ir(Ⅳ). The HOMO and LUMO energy levels for each complexes are located from the cyclic voltammogram and the absorption edge. The 10% weight reduction temperatures of the major complexes are in the range from 300 to 400oC, and suitable更多还原