QQ客服 官方微博 反馈留言

题名	树枝状铱配合物的后功能化与性能表征
作者	王漾
学位类别	博士
答辩日期	2015-05
授予单位	中国科学院研究生院
授予地点	中国科学院长春应用化学研究所
导师	王利祥
关键词	后功能化 树枝状铱配合物 双极型铱配合物 电子传输型树枝
中文摘要	基于“主客体一体化”思想的树枝状配合物由于树枝对发光核的包裹作用减小了浓度淬灭效应，因而在溶液加工型非掺杂磷光器件中具有很大发展潜力。本论文针对树枝状铱配合物的传统前功能化合成方法面临产率低和普适性差的核心问题，发展了一种树枝状铱配合物可控合成的后功能化方法，即首先合成带有羟基反应官能团的铱配合物中心核，然后通过Williamson成醚反应引入空穴传输型、双极传输型和电子传输型三类外围树枝，高效地合成了一系列具有不同功能的功能化树枝状铱配合物。主要研究内容如下： （1）采用N-苯基咔唑单元来代替经典Fréchet树枝中的苯环，构建了一类新型的空穴传输型苄醚树枝。通过后功能化方法，设计合成了从一代至四代树枝状绿光铱配合物（3NPC-G1、9NPC-G2、21NPC-G3和45NPC-G4），其中，45NPC-G4是目前文献报道的最大尺寸的铱配合物，分子尺寸为10 nm，分子量为15.9 kDa。随着树枝代数的增加，树枝状铱配合物分子间相互作用减弱，膜态下的发射光谱由3NPC-G1的540 nm蓝移到45NPC-G4的520 nm；另一方面，空穴传输能力逐渐降低。两者作用的共同结果，导致9NPC-G2（D = 6 nm）获得了最优的非掺杂器件性能，发光效率高达50.5 cd/A。 （2）通过后功能化方法，在蓝光中心核的外围引入双极性咔唑/芳基膦氧杂化树枝（B-CzPO和B-POCz），或同时引入具有空穴传输能力的咔唑树枝和具有电子传输能力的芳基膦氧树枝（B-Cz2PO1和B-Cz1PO2），设计合成了两类双极性树枝状蓝光铱配合物。单载流子器件与单层蓝光器件的研究表明，相比单极性参比化合物B-CzG2，这两类树枝型铱配合物都拥有较好的载流子传输平衡能力。非掺杂器件的最大发光效率分别为23.1 cd/A和23.3 cd/A，在1000 cd/m2的亮度下，发光效率依然保持在21.2 cd/A和22.7 cd/A，效率滚降分别为8%和2%，远远低于单极的参比化合物B-CzG2（23%）。 （3）利用后功能化方法，通过在铱配合物中心核引入具有电子传输能力的芳基膦氧树枝，设计合成了系列醇溶性红光（IrR-POG2）、绿光（IrG-POG2）和蓝光（IrB-POG2）树枝状铱配合物。其中，蓝光树枝状铱配合物IrB-POG2表现出明显的N-型传输特性，可以基于溶液工艺制备单发光层和双发光层器件，最大发光效率分别达到10.5 cd/A和17.1 cd/A。
英文摘要	Phosphorescent dendrimers with “self-host” feature have shown promising potential in non-doped solution-processed OLEDs because the peripheral dendrons can reduce the luminance quenching of the phosphorescent cores. The conventional method for synthesizing phosphorescent dendrimers involves the preparation of dendronized ligands followed by coordination with transitional metal salts. This so-called “pre-functionalization” approach suffers from problems of low yield as well as poor universality toward synthesis of diversified phosphorescent dendrimers. To solve this problem, in this dissertation, we propose a “post-functionalization” strategy to produce a series of functionalized iridium (Ir) dendrimers. Herein the hydroxyl substituted Ir-complex cores were first synthesized and then coupled through Williamson condensation with reactive dendrons containing various functional units such as hole-transporting units, bipolar units and electron-transporting units. Their synthesis, photophysical and electroluminescent properties were investigated in detail. (1) By replacing the phenyl units of the Fréchet dendrons with N-phenylcarbazole (NPC) units, a new type of polyether dendrons is constructed. Subsequently, a post-functionalization procedure, that is, coupling the polyether dendrons with a green Ir-complex core Ir(pbi)3, produces Ir dendrimers up to the fourth generation (3NPC-G1, 9NPC-G2, 21NPC-G3 and 45NPC-G4). Among them, 45NPC-G4 has a diameter of 10 nm and molecular weight of 15.9 kDa, which is the largest iridium complex reported to date. The intermolecular interactions are weakened as the generation grows. The PL spectra in thin films are blue-shifted from 540 nm for 3NPC-G1 to 520 nm for 45NPC-G4. On the other hand, the hole transport ability of the dendrimers become weaker with the increase of dendron generation. A compromise of these two aspects results in an optimal device performance for 9NPC-G2, achieving a maximum efficiency of 50.5 cd/A (56.6 lm/W, 14.8%), which is the highest efficiency for non-doped green devices up to date. (2) By introducing either arylphosphine oxide/carbazole hybridized dendrons (B-CzPO and B-POCz) or both p-type carbazole dendron and n-type arylphosphine oxide dendron (B-Cz2PO1 and B-Cz1PO2) to the blue-emitting Ir cores through post-functionalization method, two types of bipolar Ir-dendrimers have been designed and synthesized. Single-carrier devices and single-layer devices show that the bipolar dendrimers possess more balanced carrier flows than the hole-transporting analogy B-CzG2 does. The optimized devices based on B-CzPO and B-Cz1PO2 reach the maximum efficiency of 23.1 cd/A and 23.3 cd/A, respectively. Most importantly, the luminous efficiencies retain 21.2 cd/A and 22.7 cd/A at 1000 cd/m2 , corresponding to very small roll-off values of 8% and 2%, respectively, which is much lower than that of B-CzG2 (23%). (3) By using the second generation arylphosphine oxide as the electron-transporting dendron and coupling them with Ir-complex cores through post-functionalization method, a series of red, green and blue dendrimers namely IrR-POG2, IrG-POG2 and IrB-POG1 were synthesized. All these Ir-dendrimers show good solubility in alcoholic solvents, which makes them able to be used in the fabrication of all-solution-processed multilayer OLEDs. Among them, the blue-emitting dendrimer IrB-POG2 exhibits the most outstanding device perfromance with the maximum efficiency of 10.5 cd/A achieved for the single-layer device and 17.1 cd/A for the double-layer device.
语种	中文
公开日期	2016-05-03
内容类型	学位论文
源URL	[http://ir.ciac.jl.cn/handle/322003/64471]
专题	长春应用化学研究所_长春应用化学研究所知识产出_学位论文
推荐引用方式 GB/T 7714	王漾. 树枝状铱配合物的后功能化与性能表征[D]. 中国科学院长春应用化学研究所. 中国科学院研究生院. 2015.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。