2,3號位置取代之喹咢啉與旋環或三芳香胺雙重鄰位混成體於有機電致發光材料的研究

Abstract

我們利用1,2-diamino-4,5-dibromobenzene和三芳香胺融合系統以及旋環融合系統合成ㄧ系列的有機電致發光材料，由於結合雙功能性 ( bifunction ) 與偶極 ( dipolar ) 的特性，使材料之間更能有效形成光激子 ( exciton )，並且利用這兩個系統的衍生物，去做一系列在有機電致發光材料的研究和探討。 首先我們用微差掃瞄卡計(DSC)和熱重量分析儀(TGA)去量測這兩個系統的熱穩定性，在QLIMS系統中，在5號氮位置下的取代基分子量愈大使整體的分子愈穩定時，其熱穩定性會越好。對Spiro-Q系統而言，這一類的熱穩定性質不錯，其中分子量愈大，其熱穩定性就會愈好。接著對此兩系統的衍生物進行吸收、放射光譜、螢光量子產率的測量；同時也利用循環伏安法評估其氧化還原行為和測定其HOMO-LUMO能階。接著搭配合適的電子傳輸層或電洞傳輸層製作發光二極體元件，並測量其光電性質，在我們選取這些化合物中，以化合物14b所做出的元件效果最好，其最大波長為518 nm，其半波寬長只有72 nm，而且最大亮度在電流密度20 mA/cm2，Luminance Efficiency為2.35 cd/A和Power Efficiency為0.42 lm/W可達到19116 cd/m2。

QLIMS and Spiro-Q type hybrid molecular materials were prepared for applications in organic light-emitting diodes. QLIMS molecular materials were obtained by combining the iminostilbin based triarylamine (donar) and quinoxaline (acceptor) and spiro-Q molecular material were obtained by combining the dibenzosuberenone based triarylamine (donar) and quinoxaline (acceptor). These molecular material structures are confirmed by NMR and single X-ray diffraction structures. Differential scanning calorimetry and thermogravimetric analysis studies were carried out to measure the thermal stability of these molecular materials. The redox behaviors and HOMO LUMO energy differences are evaluated by the cyclic voltammetry experiments. These compounds were subjected to optoelectronic studies by fabrically bilayer OLEDs with a device configuration of ITO / NPB / compound / TPBI / LiF / Al. Among them, Spiro-m-m-phenyl-N-diphenyl (14b) led to the best device performance and exhibited maximum EL brightness (L) of 19116 cd/m2 and an operaional quantum efficiency (ηext) of 1.15 ％.