1,3,2-苯並二氮雜硼引入蒽之合成、性質探討及其在藍色有機發光二極體與陰離子偵測之應用

Synthesis and Characterization of 1,3,2-Benzodiazaboroles Substituted 10-phenylanthracene and Their Applications in Blue Fluorescent Organic Light Emitting Diodes and Anion Detection

謝鈞瀚(Chun-Han Hsieh)

指導教授 ： 梁文傑

國立臺灣大學/理學院/化學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202101652

摘要

藉由等電子體的概念，我們將硼、氮原子引入吲哚結構，硼原子的低電負度特性去調整有機分子的電性質，並整合成10個π電子共軛系統的1,3,2-苯並二氮雜硼分子，並將其作為研究之主架構。硼原子的空pz軌域同時可做為陰離子的受體，因此可產生化合物螢光性質的改變。因此，我們在主架構中不同的位置上引入有高量子產率、具TTA-UC特性的藍光基團10-苯蒽，以利運用於藍光材料中，並同時探討其和離子間的反應與變化，運用於離子辨識材料上。
透過光物理分析，可知這系列化合物之螢光落在藍光至藍綠光範圍；在熱性質分析中，所合成之化合物的熱裂解溫度皆高於元件蒸鍍所需溫度 (200 ℃)，且玻璃轉移溫度皆高於110 ℃，符合元件所需的熱性質要求。本系列化合物皆可於以Pd(OEP)作為敏料的Xylene溶液中，以低能量的綠光激發並產生高能量的藍光，而此現象可以和光物理分析圖譜的結果相呼應。
於元件表現部分，我們將五個化合物作為主發光層之非摻混材料，其中以材料NAn與dmBA表現最佳，最大亮度達1418 cd/m2與780 cd/m2，最大電流效率分別為3.78 cd/A與1.60 cd/A，外部量子效率達2.06%與2.79%。此外，材料BdpA與dmBA製作元件後具有深藍色螢光表現，也同具有穩定的放光波長。其中以TrEL光譜可以發現材料pABIZ具有良好的TTA-UC現象。
於離子辨識實驗部分中，我們發現化合物在不同離子的溶液中，會改變其光物理性質。此系列化合物對於F-與OH-的顏色變化最為快速且明顯，化合物的吸收紅移，使溶液顏色由透明轉到可見光區；螢光強度也會大幅減弱，這些變化此皆能以肉眼辨識。此外，化合物也會在加入H2PO4-與H2P2O72-後隨時間改變常溫螢光光譜曲線的現象，而這些化合物對陰離子的顏色變化顯示了此系列硼氮化合物具有作為多陰離子辨識的應用潛力。

關鍵字

硼氮吲哚 ； 有機含硼化合物 ； 1,3,2-苯並二氮雜硼 ； 蒽 ； 藍色螢光有機發光二極體 ； 三重態-三重態湮滅光子上轉換 ； 陰離子偵測

並列摘要

Boron atoms have relatively low electronegativity and vacant pz orbitals. By introducing boron atoms to molecular designs, we can adjust the electronic properties of aromatic molecules. Also, the vacant pz orbitals of boron atoms can be as anion acceptors, which means that the photophysical properties may be changed in the appearance of anions. Therefore, we replaced the C=C bond of indole with B-N bond to construct a still 10 π electron conjugated system. In this thesis, we constructed heterocyclic molecules, called 1,3,2-benzodiazaboroles, as the main structure.
We chose 10-phenylanthracene as substituents, which possess deep blue fluorescence, high quantum yield and TTA-UC properties. We substituted 10-phenylanthracene in different positions of 1,3,2-benzodiazaboroles to adjust their photophysical properties and TTA-UC efficiency to apply in light-emitting materials. At the same time, we discussed the change of photophysical properties in the appearance of anions to apply in anion sensor arrays.
According to absorption and emission spectra, these molecules emitted deep blue fluorescence and high quantum yield performance. Also, TTA-UC phenomena could be observed from emission spectra and in xylene solution with Pd(OEP). These molecules had high decomposition temperature (Td) and glass transition temperature (Tg), which meets the basic requirements of producing OLED devices.
A non-doped OLED devices using NAn and dmBA as emitter exhibited a maximun luminenscence of 1418 cd/m2 and 780 cd/m2; a maximun current efficiency of 3.78 cd/A and 1.60 cd/A; a maximun of external quantum yield (EQE) of 2.06% and 2.78% respectively. In addition, BdpA and dmBA showed deep blue fluorescence and CIE index of (0.155, 0.076) and (0.152, 0.065) respectively, and had a stable emission wavelength in different voltage. In TrEL spectra, pABIZ showed high percentage of delayed fluorescence from TTA-UC properties at high current density.
In anion detection experiments, we discovered that F- and OH- would change the photophysical properties of most of these molecules. The absorption profiles would change and new peaks were generated in the appearance of F- or OH-, making the color of solutions red-shifting to visible light and quenching their emission. Also, in the appearance of H2PO4- and H2P2O72-, the profiles of fluorescence spectra wound change upon time. The change of these molecules shows that they have the potential to apply in sensor arrays for multiple anions.

並列關鍵字

B-N indoles ； Organoboron ； 1,3,2-benzodiazaborole ； Blue fluorescent OLED ； TTA-UC ； Anthracene ； Anion detection

參考文獻

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