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河南省化学会2016年学术年会

作者： Li Min Wang Xiao Sheng Li xiang Hua Zhao College of Chemistry and Chemical Engineering Xinyang Normal University

Phosphorescent organic light-emitting diodes(Ph OLEDs) are outstanding science the potential of100% internal quantum resulted from strong spin–orbit coupling caused by heavy atoms, which could lead to an efficient intersystem crossing to harvest both triplet and singlet excitons. However, phosphor emitters often suffer self-quenching and triplet-triplet annihilation at high doping concentration.Ph OLEDs often employ host-guest system to resolve this problem. To date, triphenylamine(TPA) and carbazole derivatives are most widely employed as host materials for Ph OLEDs due to their high triplet energy level, sufficient hole transporting property, and wide energy gap. Nevertheless, the twisted molecule struture of TPA is detrimental to obtain high thermal and morphological stabilities host materilas. Therefore, many efforts have been made to improve thermal and morphological stabilities with high triplet energy level of the TPA host.Although many TPA containing hosts used for Ph OLEDs with high performance at low dopi ng ratios have been reported, rare TPA containing hosts with wide heavy dopant range for stab le perfor-mance Ph OLEDs have been reported due to the inherent triplet–triplet annihilation and concentration quenching of phosphorescent emitters. The low dopant Ph OLEDs could suppress triplet–triplet annihilation and concen-tration quenching of phosphor guests in solid state but und ergo time-consuming and tedious process. Moreover, the slight fluctuation of doping ratio proba bly leads to an obvious change of device performance, which would increase the process diffic ulty and production cost, and reduce device repeatability. In order to resolve this problem, one of the effective strategies is to design and synthesize bulky host with large steric hin-drance to simplify fabrication process and improve device repeatability. In this paper, we demonstrate the facile synthesis of a novel 9-(pyridyl-2-yl)-fluoren-9-ol(Py FOH)/triarylamine hybrid(tris[4-(9-(py ridine-2-yl)-fluoren-9-yl)phenyl]- amine, TPy FTPA)

关键词： steric hindrance triphenylamine PhOLEDs high doping concentration

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A Bulky Pyridinylfluorene/Triphenylamine Hybrid Used as Host Material for Heavily-Doped Blue Electrophosphorescent Devices

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Chinese Journal of Chemistry 2016年第4期34卷 397-402页

作者： Xianghua Zhao Yukun Wu Li Zhou Nana Wu Lin Tang Yi Zhao Xiaosheng Li Dongxue Ding Hui Xu College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 Henan China State Key Laboratory on Integrated Optoelectronics College of Electronics Science and Engineering Jilin University Changchun Jilin 130012 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education Heilongjiang University Harbin Heilongfiang 150080 China

In this work, a novel molecule pyridinylfluorene/triphenylamine hybrid （TPyFTPA） with bulky steric hindrance effects has been synthesized successfully by substituting 9-（pyridine-2-yl）-fluoren-9-yl with triphenylamine （TPA） via Friedel-Crafts reaction, which possesses good thermal stability and triplet energy （ET） of 420 ℃ with 5% weight loss and 2.86 eV, respectively. Moreover, the bulky steric hindrance material shows high stable morphology by heating to 200 ℃ without finding melting phenomena and crystallization that is demonstrated by differential scanning calorimetry （DSC） curve. The bulky pyridinylfluorene end-capped TPA has been used as host material for blue phosphorescent organic light-emitting diodes （PhOLEDs） with maximum external quantum efficiencies （EQEs） of 2.7%, 3.7%, and 3.5%, at the doping ratios of 10%, 30%, and 40%, respectively. The performances of TPyFTPA-based blue PhOLEDs own wide concentration ranging from 10% to 40%, which indicates the bulky TPyFTPA might be a potential candidate for inexpensive products with simplifying process for the applications in full-color display and solid state lighting.

关键词： steric hindrance triphenylamine PhOLEDs high doping concentration

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Carbazole-endcapped Spiro[fluorene-9,9＇-xanthene] with Large Steric Hindrance as Hole-transporting Host for Heavily-doped and High Performance OLEDs

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Chinese Journal of Chemistry 2015年第8期33卷 955-960页

作者： Xianghua Zhao Yukun Wu Nannan Shi Xiaoyu Li Yi Zhao Mingli Sun Dongxue Ding Hui Xu Linghai Xie College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang Henan 464000 China State Key Laboratory on Integrated Optoelectronics College of Electronics Science and Engineering Jilin University 2699 Qianjin Street Changchun Jilin 130012 China China Key Laboratory for Organic Electronics & Information Displays (KLOEID) Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing Jiangsu 210046 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education Heilongjiang University Harbin Heilongjiang 150080 China

In this work, we designed and synthesized a novel spirocyclic compound functionalized spiro[fluorene-9,9＇- xanthene] with carbazole group （2-carbazolyl-spiro[fluorene-9,9＇-xanthene], SFX-Cz） via Friedel-Crafts and Ullmann reaction, which is expected to own high thermal and morphological stability, and good carrier injection/ transporting properties due to the excellent hole transporting characteristics of carbazole and cruciform structure of spiro[fluorene-9,9＇-xanthene]. The carbazole end-capped spiro[fluorene-9,9＇-xanthene] SFX-Cz based PhOLEDs with Flrpic as phosphor emitter have been researched by varying dopant concentration, which exhibit the maximum EQEs of 8.9%, 7.4%, 9.1%, and 4.7% with the doping increasing from 10% to 50%. The higher performance PhOLEDs are independent on concentration variation from 10% to 30%, which suggests the bulky steric hindrance of SFX-Cz might be a potential canditate for high performance and inexpensive device with simplified process.

关键词： steric hindrance spirocyclic compound heavily-doped PhOLEDs inexpensive device

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无金属催化条件下吡咯并喹啉的合成和1,2,3-三氮唑类衍生物的光电性能研究

无金属催化条件下吡咯并喹啉的合成和1,2,3-三氮唑类衍生物的光电...

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作者：刘成国苏州大学

学位级别：硕士

含氮杂环是一类重要的杂环化合物,它广泛存在于天然产物和功能分子中,其功能衍生物的合成及性能研究是当前有机合成和材料化学领域的研究热点。本论文开发了一种无金属催化下异腈与邻氨基亚甲基环丙烷合成喹啉并吡咯类衍生物的方法;并基... 详细信息

含氮杂环是一类重要的杂环化合物,它广泛存在于天然产物和功能分子中,其功能衍生物的合成及性能研究是当前有机合成和材料化学领域的研究热点。本论文开发了一种无金属催化下异腈与邻氨基亚甲基环丙烷合成喹啉并吡咯类衍生物的方法;并基于1,2,3-三氮唑设计合成了一系列双极主体材料,对其作为主体材料在有机发光二极管(OLED)中的应用进行了详细研究。具体内容包括以下两部分:第一部分(第二章)我们开发了一种无金属催化的吡咯并喹啉骨架的新方法。该方法利用碘/过氧化氢异丙苯(I2/CHP)催化2-氨基芳基亚甲基环丙烷/环丁烷与异腈发生加成反应,经过碳二亚胺中间体,并在热引发下发生6л-电环化反应,再经过[3+2]环加成生成吡咯并喹啉或哌啶并喹啉的衍生物。该反应无须金属催化,绿色环保经济廉价;在55 ℃下空气氛围中即可反应,条件温和;多种底物都能得到中等至良好的产率,高效普适。第二部分(第三章)我们设计合成了一系列以非对称的1,2,3-三氮唑为核心的有机光电主体材料,并通过测试、分析它们的性能,初步探索出1,2,3-三氮唑为核心的主体材料的结构与性能的关系。在此基础上,我们实现了对分子结构精细可控调节——设计合成了新型双极主体磷光材料dDPAmTAZ和dN-PhCzmTAZ,深入研究了材料的性能并将其制备成磷光OLED器件。由于在苯环的间位偶联,有效打断分子共轭,两者三线态能级(ET)分别高达2.84 eV和2.74 eV;由于1,2,3-三氮唑的非对称性,导致材料具有独特的电子性能。以dN-PhCzmTAZ做主体制备的器件,主要性能电流效率/功率效率/外量子效率(CE/PE/EQE)分别为29.4cd/A、17.11m/W和8.9%,都明显优于以对称的1,2,4-三氮唑衍生物为主体制备的器件。

关键词：无金属催化异腈吡咯并喹啉 1,2,3-三氮唑 PhOLEDs

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A novel bulky 1,3,4-oxadiazole/spiro[fluorene-9,9′-xanthene] hybrid used as solution-processable host for green TADF devices

A novel bulky 1,3,4-oxadiazole/spiro[fluorene-9,9′-xanthene...

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河南省化学会2020年学术年会

作者： Yi-JieYang Xiang-Hua Zhao College of Chemistry and Chemical Engineering Xinyang Normal University

Organic light-emitting diodes (OLEDs) have been developed for several decades since the pioneering work of Tang and Vanslyke in 1987, due to their enormous potential applications in full-color displays and white solid-state lighting.Thanks to the continuous devotions of numerous investigators,the significant advancement of phoshpor emitters with 100%IQE was first reported by Thompson and Forrest,which could harvest both signet and triplet excitons due to spin-orbit coupling caused by heavy metals.Yet,the phosphorescent precious-metal complexes often suffer from instability in full-color display and white solid-state lighting.Moreover,due to the rather expensive and limited global resources of noble metals,purely organic thermally activated delayed fluorescence (TADF) metal-free emitters have increasingly attracted attention due to its high efficiency and low cost in the past few years.For TADF emitters,they could not only harvest both triplet and singlet excitons through upconversion caused by thermally activated delayed fluorescence giving theoretical maximum IQE up to100%but also are inexpensive without using noble-metal complexes and comparable stability in practical application compared to that of phosphorescent OLEDs.In order to achieve high efficiency,TADF emitters also should be dispersed into a suitable host to suppress concentration quenching through triplet-triplet annihilation and triplet-polaron quenching in solid state.Therefore,an appropriate host is very important to realize high performance TADF OLEDs.3D bulky host materials are often designed and synthesized to resolve these problems for high-efficient TADF OLEDs.In this work,a novel bulky 1,3,4-oxadiazole-based spirocyclic compound 2,5-bis(2-spiro[fluorene-9,9′-xanthene]-7-yl)phenyl)-1,3,4-oxadiazole (D[2-SFXP]-o-OXD) has been synthesized.Two green TADF OLEDs hosted D[2-SFXP]-o-OXD and D[2-SFXP]-o-OXD:m CP by solution-processing techniques with maximum current efficiency (CE) and EQEs of 15.2 cd A/4.8%and 25.9 cd A/8.5%,respectively.The electrol

关键词： steric hindrance triphenylamine PhOLEDs high doping concentration

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