芳香取代吡咯雙極子螢光分子的合成及螢光特性 = Synthesis an...
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  • 芳香取代吡咯雙極子螢光分子的合成及螢光特性 = Synthesis and Characterization of Ambipolar Aryl-Substituted pyrrole Fluorophores
  • Record Type: Language materials, printed : monographic
    Paralel Title: Synthesis and Characterization of Ambipolar Aryl-Substituted pyrrole Fluorophores
    Author: 陳柏志,
    Secondary Intellectual Responsibility: 國立高雄大學
    Place of Publication: [高雄市]
    Published: 撰者;
    Year of Publication: 2011[民100]
    Description: 187面圖,表 : 30公分;
    Subject: 吡咯
    Subject: pyrrole
    Online resource: http://handle.ncl.edu.tw/11296/ndltd/63938622164666047830
    Notes: 參考書目:面106-109
    Notes: 103年12月16日公開
    Summary: 對於有機發光二極體來說,藍光材料及電子傳輸材料一直是開發的重點,本研究以吡咯(pyrrole)為重心,分別在吡咯主體的2、5號位或是3、4號位取代上導入電子給體以及電子受體,合成具有同時傳遞電子以及電洞能力的雙極子分子。研究中利用吡啶以及咔唑官能基在不同位置所造成的放光特性了解這些電子給體以及受體最佳的取代位置,結果證實將電子給體置於3、4號位置而將電子受體受體置於2、5號位置所得到的螢光量子效率最大(~80%),而其以及光色最為符合深藍色螢光(FL ~ 438 nm)。為了進一步瞭解這類雙極子螢光分子的光電特性,本研究合成一系列具有不同電子受體的雙極子螢光分子,並利用光學性質以及電學性質的研究評估這些分子的光電特性。研究結果顯示這類雙極子螢光分子除了本身是具有高螢光量子效率的深藍色螢光的特性外,仍具有許多獨特的光電特性。首先,這一系列分子可以在不影響放光光色的情況下有效的降低分子的LUMO值至3.4 eV左右,且其HOMO仍可維持在5.4 eV。這些結果與陽極常用之ITO玻璃(5.0 eV)以及陰極常用的鎂(3.7 eV)或是鋁金屬(4.3 eV)的費米能階相當接近,有利於電子、電洞的注入。其次,本研究所合成之雙極子螢光分子除了Cz-oxf外,其它分子具有不易產生固態聚集的特性,因此其在二氯甲烷溶液下的光色與固態下的光色幾乎一樣。另外,本研究也探討這類雙極子螢光分子在磷光主體材料的可行性。結果發現這些雙極子螢光分子的三重態能量仍有不錯的表現(ET ~ 2.4 eV)可作為綠光及紅光摻雜物的主體材料。研究中也發現這些材料在導入電子給體(咔唑)前後的三重態能量變化不大(ET由2.5 降低至2.4 eV),此結果對於雙極子磷光主體材料的設計具有相當大的幫助。 Organic light emitting diode offer great application potentials for flat panel and solid-state lighting. However, there are far fewer stable blue-emitting fluorophores have been developed because of their intrinsically HOMO-LUMO gap. In this work, a series of novel ambipolar fluorophores with deep-blue fluorescence (FL~440 nm) were developed. The optimal substitution sites which the donor and acceptor groups attached on were investigated by introducing pyridyl; electron-acceptor, and carbazole; electron-donor onto the central pyrrole core. Highly quantum efficiency(~80%) bipolar fluorophores were acquired by grafting some electron-donor onto the pyrrole platform at the 2,5- positions and electron-acceptor groups at the 3,4-positions, respectively.There are some interesting electrooptical characters were found in the bipolar fluorophores. There are little aggregation-induced bathochromic emission were found in the fluorophores except for 2Cz-oxa. The fluorophores emit deep-blue fluorescence in the range of 426~ 454 nm increasing as the polarity of solvents. Most of the bipolar fluorophores emitting in the solid films are similar to those emitting in THF solution except for 2Cz-oxa. Moreover, The HOMO/LUMO energy levels can be tuned easily without influencing the deep-blue fluorescence. All the HOMO energy levels of the fluorophores were controlled closing 5.4 and LUMO levels closing 3.4 eV. The HOMO/LUMO energy levels were close to the corresponding electrode Fermi leves (work function of ITO anode is 4.8~5.0 eV and of Mg and Al cathodes are 3.7 eV and 4.3 eV, respectively). Phosphorescence properties of the ambipolar fluorophores were also studied in this work. As a result, the triplet energy gap of the bipolar fluorophores, estimated from the high energy emission maximum of the phosphorescence spectrum are arrange from 2.42 to 2.45 eV. The triplet energies of the bipolar fluorophores are close to that of the electron-transporting-only fluorophores ppn and hole-transporting-only npCz of 2.56 eV (484 nm). The result indicates that the triplet energies of the pyrrole-based fluorophores are influenced slightly by introduction of the terminal functional groups. Stable glassy morphologies were found in the bipolar fluorophores. The Tg value are as high as more thane 150 °C and the Td values more than 450 °C. Sterically congest pyrrole platform restrict intermolecular packages and meta-direction structure provide the bipolar fluorophores more different conformers.From the investigation of this work, the pyrrole-based bipolar fluorophores are useful fluorophores. They maybe have potential to solve the stability of the blue light emitting devices.
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310002501800 博碩士論文區(二樓) 不外借資料 學位論文 TH 008M/0019 421202 7544.1 2011 一般使用(Normal) On shelf 0
310002501818 博碩士論文區(二樓) 不外借資料 學位論文 TH 008M/0019 421202 7544.1 2011 c.2 一般使用(Normal) On shelf 0
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