具有电子传输特性的Be金属配合物作为磷光主体材料的电致发光性能

采用具有优良电子传输特性的铍金属配合物二合铍(Ⅱ)(Bempp)作为磷光客体材料二(2-苯基吡啶)(N,N'-二异丙基苯甲脒)合铱(Ⅲ)(PPP)的主体材料制备磷光电致发光器件. 与经典的空穴传输型主体材料4,4'-二(N-咔唑)联苯(CBP)相比, Bempp更有利于空穴、 电子的注入及传输的平衡, 与PPP间存在更高效的能量转移. 该器件的各项性能指标, 包括最大效率和流明效率(63.1 cd/A和54.0 lm/W), 均明显高于采用CBP作为主体材料的磷光器件.     

基于联咔唑为骨架的双极主体材料的合成及其在有机电致发光器件中的应用

咔唑类衍生物具有良好的空穴传输性能和较高的三重态能级,在有机电致发光器件中一般用来构建空穴传输材料和主体材料。本文通过在联咔唑的3和6位引入具有电子传输能力的氰基,设计合成了一种以双咔唑二聚体为分子骨架的新型双极性有机电致发光主体材料6,6’-双氰基-9,9’-二苯基-3,3’-联咔唑（BCzDCN）,研究了其发光性能、热稳定性和电化学性质。低温磷光发射光谱测试表明BCzDCN的三重态能级高于传统的天蓝色磷光掺杂材料双（4,6-二氟苯基吡啶-N,C²’）吡啶甲酰合铱（FIrpic）。以BCzDCN为主体材料,FIrpic和双（4-苯并噻吩）[3,2-C]吡啶-N,C²’）乙酰丙酮合铱（PO-01）分别为蓝色和黄色磷光掺杂材料,制备了蓝色和白色有机磷光发光二极管器件。器件的最大电流效率分别达到34.6 cd/A和59.0 cd/A。并且在1000 cd/m²亮度下的效率滚降仅有4.1%和5.1%。     

超薄铝/碳酸锂修饰氧化铟锡阴极制备蓝色磷光反转底发光有机发光二极管

在氧化铟锡（ITO）阴极上依次蒸镀2 nm铝和2 nm碳酸锂（Li2CO3）薄膜作为电子注入层,成功制备出器件结构为ITO/Al/Li2CO3/SPPO13/SPPO13∶FIrpic/TCTA/MoO3/Al(SPPO13：2,7-双（二苯基磷）-9,9′-螺二[芴];FIrpic：双(4,6-二氟苯基吡啶-N,C2)吡啶甲酰合铱;TCTA：4,4′,4″-三(咔唑-9-基)三苯胺)的蓝色磷光反转底发光有机发光二极管（IBOLED）。 结果表明,Al/Li2CO3作为电子注入层可以有效降低ITO与有机材料之间的电子注入势垒,蓝色磷光IBOLED的起亮电压由11 V降至4.2 V,器件的发光效率也得到有效提高。 蓝光磷光IBOLED的最大电流效率与功率效率分别达到了28.2 cd/A和19.6 lm/W,制备出的反转结构器件性能可与传统正置结构比美,说明Al/Li2CO3可以作为反转有机发光二极管优良的电子注入层。     

含吡啶基团的双极主体材料的合成、性能与蓝光电致磷光器件研究

吡啶类衍生物具有较好的电子传输性能和较高的三线态能级,在有机电致发光中一般用来构建电子传输材料或主体材料中的电子传输单元.本文通过将吡啶的2,6位与三苯胺或N-苯基-咔唑的邻位连接设计合成了两个基于吡啶的双极主体材料DTPAPPy和DCzPPy.它们的三线态能级分别为2.64和2.70eV.以它们作为主体材料制备的基于Firpic的蓝光磷光器件最大电流效率分别为15.4和25.3cd/A.     

一种基于咔唑的新型磷光主体材料的合成及光电性能

设计并合成了一种基于咔唑的新型的磷光主体材料, 即9-(6-(9-咔唑基)己基)咔唑(hCP), 对其结构及性能进行了表征. 研究结果表明: hCP分子中两个咔唑与烷基链是非共平面的, 由于长烷基链的缠绕, 因而具有较高的三线态能级(3.01 eV)和较高的玻璃化温度(93℃); 以hCP为主体材料, 与绿光磷光染料三(2-苯基吡啶)合铱(Ir(ppy)₃)掺杂作为发光层, 制备了磷光电致发光器件, 其器件的最大电流效率为15.1 cd·A^-1, 相对于4,4'-N,N'-二咔唑基联苯(CBP)为主体材料的参考器件, 显著提高了34.8%.     

带烷氧基的苯基蒎烯吡啶铱配合物在聚合物电致发光器件中的应用研究

采用旋涂法将一组带烷氧基的苯基蒎烯吡啶铱(Ⅲ)配合物(Ir(RO-pppy)₃)磷光材料掺杂到PVK中,制作出了聚合物电致发光器件:ITO/PE-DOT:PSS(40 nm)/PVK_0.7:PBD_0.3:(x%.)Ir-complex(80 nm)/CsF(1.5 nm)/Mg:Ag(200 nm).实验结果表明,带有长烷氧基链配体的铱(Ⅲ)配合物能表现出更好的器件行为,当掺杂浓度为3.2%时,器件的最高发光效率达19.9 cd/A(7.8 lm/W,9.1V),CIE为(0.20,0.56);器件最大亮度为15700 cd/m²(8.4V).通过对这组铱(Ⅲ)配合物的光物理行为及电化学性能的研究,考察了主体材料与配合物之间的能级配置以及能量转移的机理.     

基于闭环二苯醚与磷氧基团的主体材料的合成及其在蓝色磷光有机发光二极管中的应用

本文通过多步有机反应制备了化合物9-苯基-9′-（4-二苯基氧化膦）苯基-氧杂蒽[diphenyl（4-（9-phenyl-9H-xanthen-9-yl）phenyl）phosphine oxide,DPPO],低温磷光发射光谱测试表明该化合物具有高的三线态能级（2.88eV）,它可以作为天蓝色磷光发光材料双（4,6-二氟苯基吡啶-N,C2）吡啶甲酰合铱[bis（3,5-difluoro-2-（2-pyridyl）phenyl-（2-carboxypyridyl）iridium（Ⅲ）,FIrpic,ET=2.62eV]的主体材料.将主体材料DPPO用于蓝色磷光有机发光二极管中,该器件在100cd/m2的亮度下,电流效率和流明效率分别达到30.6cd/A和19.2lm/W,最大外量子效率达到13.6%.     

基于咔唑-三唑的新型主体材料及天蓝光有机电致磷光器件

本研究针对蓝光主体材料相对缺乏的现状,利用有机电致磷光器件高效率的优势,选择1,2,4-三唑为电子传输功能基团、咔唑为空穴传输功能基团,设计、制备了新型主体材料oCzTz。通过邻位取代方式实现了分子立体构型高度扭曲,从而使分子的三重态能量达到3.01eV;oCzTz具有较高的热分解温度(353℃)和玻璃化转变温度(110℃);量化计算显示,分子的前线轨道在咔唑和三唑基团之间高度分离。以oCzTz为主体、以FIrpic为发光客体的天蓝光电致磷光器件启亮电压为3.4V,电流效率和功率效率分别高达37.2cd·A-1和29.2lm·W-1,是以TPBI为电子传输层的同类器件的最高效率之一。     

侧链含金属铱配合物的电磷光白光聚合物

设计了一系列新型芴-咔唑电磷光共轭聚合物.通过共价键将双(2-(9,9-二乙基-9H-芴-2-基)吡啶-N,C2’)合铱(III)(Ir Fpy)接枝到3,6-二溴咔唑的N-烷基侧链,采用Suzuki缩聚反应合成了铱配合物(Ir Fpy)含量分别为0.25 mol%,0.5 mol%和1 mol%的聚合物PF-Ir Fpy.当引入的配合物Ir Fpy含量为1 mol%时,得到的共轭聚合物发射色坐标为(0.44,0.56)的黄光.随着接枝的铱配合物Ir Fpy在共轭聚合物中含量降低,作为主体的聚(9,9-二辛基芴)蓝光发射不能被完全淬灭,得到共聚物同时发射主体蓝光及客体铱配合物黄光的单分子白光共轭聚合物.共聚物发光器件结构为ITO/PEDOT:PSS(50 nm)/polymer+PBD(30 wt%)(80nm)/Ba(4 nm)/Al(150 nm)[氧化铟锡/苯磺酸掺杂聚乙烯基二氧噻吩/聚合物+(2,4-二苯-5-4-叔丁基苯-1,3,4-噁二唑)(w=30%)/钡/铝],基于共聚物PF-Ir Fpy025的器件流明效率为3.97 cd/A,色坐标为(0.34,0.34),非常接近于标准白光发射的色坐标(0.33,0.33).为了研究采用共聚物PF-Ir Fpy025和PF-Ir Fpy05制备的白光器件的光谱稳定性,测试了外加电压在8~13 V范围内的EL光谱,当外加电压从8 V升高到13 V时,两个EL器件都表现出了良好的EL光谱稳定性.研究结果表明,在共轭聚合物侧链上引入螯合金属铱配合物单元是实现高效、稳定的白光电致磷光器件的有效方法之一.     

含二苯胺2,6-二咔唑基吡啶共轭化合物的合成

以咔唑,2,6-二溴吡啶和二苯胺为原料,经Ullmann和碘代反应合成了4个含二苯胺2,6-二咔唑基吡啶共轭化合物:3-二苯胺基-2,6二咔唑基吡啶,3,3’-二(二苯胺基)-2,6-二咔唑基吡啶,3,3’,6-三(二苯胺基)-2,6-二咔唑基吡啶和3,3’,6,6’-四(二苯胺基)-2,6-二咔唑基吡啶,其结构经1H NMR和IR确证。     

New C2-symmetric 2,2′-bipyridine crown macrocycles for enantioselective recognition of amino acid derivatives

A series of new C₂-symmetric 2,2′-bipyridine-contaning crown macrocycles 1-4 has been developed for enantiomeric recognition of amino acid derivatives. These new macrocycles have been showed to be strong complexing agents for primary organic ammonium salts (with K up to 4.83×10⁵ M⁻¹ and −ΔG₀ up to 32.4 kJ mol⁻¹) and also useful chromophores for UV-vis titration studies. These macrocyclic hosts exhibited enantioselective binding towards the (S)-enantiomer of phenylglycine methyl ester hydrochloride (Am1) with K_(S)/K_(R) up to 2.10 (ΔΔG₀=−1.84 kJ mol⁻¹) in CH₂Cl₂ with 0.25% CH₃OH. The structure-binding relationship studies showed that the aromatic subunit and the ester group of the ammonium guests are both important for good enantioselectivity. In addition, the host-guest complexes have been studied using various NMR experiments.     

Structure and Kinetics of Desolvation of 2-Hexanone Inclusion Compounds of the Hexapedal Hosts, Hexakis(3-hydroxy-3,3-diphenyl-2-propynyl)benzene and 1,2,3,5,6,7-Hexakis(3-hydroxy-3,3-diphenyl-2-propynyl)naphthalene

The 2-hexanone inclusion compounds of hexakis(3-hydroxy-3,3-diphenyl-2-propynyl)benzene and 1,2,3,5,6,7-hexakis(3-hydroxy-3,3-diphenyl-2-propynyl)naphthalene have been prepared and characterised by single crystal X-ray diffraction and thermal analysis. The kinetic parameters and mechanisms for the desolvation reaction have also been determined for both compounds.     

Crystalline complexes of N,N'-ditritylurea (DTU) and N-tritylurea (NTU) hosts with molecular guests

This paper reports crystalline complexes of the new hosts N,N'-ditritylurea (DTU) and N-tritylurea (NTU) with various uncharged molecular guests. The crystal structures of the following complexes were elucidated by single crystal X-ray diffraction analysis at 115^oK: (I) 1:1 DTU-propanamide — space group C2/c, a=15.839Å, b=9.088Å, c=24.584Å, =111.05^o, Z=4; (II) 1:1 DTU-ethyl N-acetylglycinate — space group P1, a=9.010Å, b=10.800Å, c=19.810 Å, =105.29^o =94.33^o, =93.03^o, Z=2; (III) 2:1 NTU-N, N-dimethylformamide — space group Cc, a=29.614Å, b=8.906Å, c=16.127Å, =121.04^o, Z=4. The three crystal structures are stabilized mainly by a cooperative effect of hydrogen bonding between amide fragments displaced along the shortest axis of each crystal. This interaction occurs between host and guest in complexes I and II, and between host and host in complex III. The latter also represents a cage-type clathrate in which the guest molecules are accommodated in voids between the hydrophobic fragments of four neighboring NTU hosts. On the other hand, complexes of DTU are characterized by a more specific interaction between the two components, each guest molecule being inserted between two adjacent hosts (related by translation) and strongly bound to them via hydrogen bridges. These results illustrate a useful concept in the design of molecular species which can be potential hosts upon crystallization with neutral molecular guests. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82022 (7 pages).     

Benzimidazobenzothiazole‐Based Bipolar Hosts to Harvest Nearly All of the Excitons from Blue Delayed Fluorescence and Phosphorescent Organic Light‐Emitting Diodes

Much effort has been devoted to developing highly efficient organic light‐emitting diodes (OLEDs) that function through phosphorescence or thermally activated delayed fluorescence (TADF). However, efficient host materials for blue TADF and phosphorescent guest emitters are limited because of their requirement of high triplet energy levels. Herein, we report the rigid acceptor unit benzimidazobenzothiazole (BID‐BT), which is suitable for use in bipolar hosts in blue OLEDs. The designed host materials, based on BID‐BT, possess high triplet energy and bipolar carrier transport ability. Both blue TADF and phosphorescent OLEDs containing BID‐BT‐based derivatives exhibit external quantum efficiencies as high as 20 %, indicating that these hosts allow efficient triplet exciton confinement appropriate for blue TADF and phosphorescent guest emitters.     

Formation of Self‐Templated 2,6‐Bis(1,2,3‐triazol‐4‐yl)pyridine [2]Catenanes by Triazolyl Hydrogen Bonding: Selective Anion Hosts for Phosphate

We report the remarkable ability of 2,6‐bis(1,2,3‐triazol‐4‐yl)pyridine ( btp ) compounds 2 with appended olefin amide arms to self‐template the formation of interlocked [2]catenane structures 3 in up to 50 % yield when subjected to olefin ring‐closing metathesis in CH₂Cl₂. X‐ray diffraction crystallography enabled the structural characterization of both the [2]catenane 3 a and the non‐interlocked macrocycle 4 a . These [2]catenanes showed selective triazolyl hydrogen‐bonding interactions with the tetrahedral phosphate anion when screened against a range of ions; 3 a , b are the first examples of selective [2]catenane hosts for phosphate.     

A Simple Correlation between the Structures of Different Crystal Modifications of a Given Host–Guest Complex and their Crystallization Temperatures

The formation of different crystal modifications of a given host-guest complex depending on the crystallization temperature (pseudopolymorphism) is studied. It is shown that such pseudopolymorphism is a characteristic feature of versatile host compounds. A very important rule for host-guest chemistry is derived from the results of the X-ray structural investigations of pseudopolymorphs: the higher the crystallization temperature of the modification the more closed is the space occupied by guest molecules. On the basis of the formulated rule a recommendation for the topological control and solution of some central problems of supramolecular chemistry is proposed.     

NOVEL SUPRAMOLECULAR DERIVATIVES CONTAINING TWO R3Sn+ (R = Me,n-Bu,or Ph) CONNECTING UNITS: THE FORMATION OF NOVEL HOST–GUEST SYSTEMS BY THE FACILE ENCAPSULATION OF GUEST THIOPHENE COMPOUNDS

New supramolecular complexes [(Me ₃ Sn)(Ph ₃ Sn) ₂ Fe(CN) ₆ ] (I) and [(n-Bu ₃ Sn)(Ph ₃ Sn) ₂ Fe(CN) ₆ ] (II) are readily accessible by straightforward self-assembly of [Fe(CN) ₆ ] ^3? and hydrated R ₃ Sn⁺/R′ ₃ Sn ⁺ ions (R = Ph, and R′ = Me or n-Bu). The structural characterization of (I) and (II) is compared with well-documented supramolecular complex containing only Ph ₃ Sn ⁺ unit, [(Ph ₃ Sn) ₃ Fe(CN) ₆ ]. These novel compounds have wide internal cavities capable of encapsulating voluminous organic compounds, and they behave as host acceptors forming charge transfer complexes (CTC). Thiophene compounds acting as guest donor species are encapsulated within the cavities of the three-dimensional (3D) supramolecular hosts. The structure and physical properties of these hosts and host–guest systems were studied by X-ray powder diffraction, IR, UV/Vis., and magnetic measurements.     

近年来OLED中双极性主体材料的研究进展在专利中的反映

双极性主体材料是目前提高电致发光器件发光效率的关键材料.本文从双极性主体材料的构造原理出发,提出了一种独到的结构特征分类方式,以结构特征及其演变过程为主线梳理了近年来这个领域的专利技术,并归纳提炼出目前这类材料在结构设计方面的主要构思,文末还对该领域的发展前景进行了展望.     

Synthetic Receptors for the High‐Affinity Recognition of O‐GlcNAc Derivatives

The combination of a pyrenyl tetraamine with an isophthaloyl spacer has led to two new water‐soluble carbohydrate receptors (“synthetic lectins”). Both systems show outstanding affinities for derivatives of N‐acetylglucosamine (GlcNAc) in aqueous solution. One receptor binds the methyl glycoside GlcNAc‐β‐OMe with K_a≈20 000 m ^?1, whereas the other one binds an O‐GlcNAcylated peptide with K_a≈70 000 m ^?1. These values substantially exceed those usually measured for GlcNAc‐binding lectins. Slow exchange on the NMR timescale enabled structural determinations for several complexes. As expected, the carbohydrate units are sandwiched between the pyrenes, with the alkoxy and NHAc groups emerging at the sides. The high affinity of the GlcNAcyl–peptide complex can be explained by extra‐cavity interactions, raising the possibility of a family of complementary receptors for O‐GlcNAc in different contexts.