摘要
本研究探討螺旋狀聚茀系高分子其側鏈及鏈末端皆導入載子傳輸基團之電致發光行為，並摻雜橘黃光、紅光小分子客體而製作成電激發白光、紅光元件。本研究分為三個部份，茲分述如下。 首先，利用聚茀系高分子為主體其側鏈以非共軛方式接上三苯胺 (具電洞收集效應) 與咔唑 (傳輸橋樑) 基團，使單一種分子鏈即具有梯度下降HOMO能階 (即TPA-Cz-sPF)，經摻雜螢光橘黃光色材料(5,6,11,12)-Tetraphenylnaphthacene (rubrene) 作為白光元件之發光層，其發光效率為21.07 cd/A (8.96%)，亮度為17,431 cd/m2，為現有白光高分子元件中之最高者。 第二部分，將上述漸進式能階概念延伸至同一側鏈上，並於其末端導入電子傳送基團3-(4-phenyl)-4-phenyl-5-(4-tert-butylbenzene)-1,2,4-triazole (TAZ) (即50GsPF-end-TAZ)，以提升電荷收集能力，此藍光高分子之電致發光效率為6.08%，亮度為10,131 cd/m2，此深藍光CIE值為(0.161, 0.052)，文獻中少見CIE座標y值低於此值0.052。 第三部分，我們將此深藍光高分子 (50GsPF-end-TAZ) 當主體材料，摻入磷光紅光小分子客體Bis(1-phenylisoquinoline) (acetylacetonate)iridium(III) (Ir(piq)2(acac)) 2wt%作為紅光元件之發光層，其電致發光效率為9.92% (12.06 cd/A)，亮度為6,372 cd/m2，CIE值為(0.67, 0.33)，非常接近國際顯示器標準的飽和紅色。
並列摘要
This study involves polyspirofluorenes (sPF) modified by incorporation of charge transporting moieties on side-chain and chain-end to facilitate hole and electron injections. We investigate their electroluminescence behaviors with and without doping with orange fluorescent and red phosphor small molecules as the guest to obtain white and red emission devices. Three parts are included in this thesis. Firstly, by incorporation of triphenylamine (as hole receiver) and carbazole (as transporting bridge) as side-chain of sPF to yield TPA-Cz-sPF, balanced bipolar fluxes and charge mobilities can be realized. By using TPA-Cz-sPF as host material and (5,6,11,12)-Tetraphenylnaphthacene (rubrene) as guest material, single layer white emission LED is obtained having high efficiency of 21.07 cd/A (8.96%), and high luminance of 17,431 cd/m2. The present efficiency is the highest among reported white PLEDs. Secondly, we further modify sPF by incorporation of TPA and Cz on the same side-chain and of electron deficient 3-(4-phenyl)-4-phenyl-5-(4-tert-butylbenzene)-1,2,4-triazole (TAZ) group on polymer chain-end. The designed polymer exhibits improved bipolar injection transport capabilities and deeper blue emission as compared to that without chain-end modification. Single layer LED based on 50GsPF-end-TAZ achieves high efficiency of 6.08%, high luminance of 10,131 cd/m2, and deep blue emission with CIE (1.161, 0.052), revealing the present molecular design is a powerful methodology. Thirdly, We utilize the deep blue polymer 50GsPF-end-TAZ as host material, and dope with 2wt% red small molecule Bis(1-phenylisoquinoline) (acetylacetonate)iridium(III) (Ir(piq)2(acac)). Its single layer LED achieves high efficiency of 9.92% (12.06 cd/A), high luminance of 6,372 cd/m2, and red emission with CIE (0.67, 0.33) which is very closely to 1931 Commission International de l’Eclairage coordinate (CIEx,y 1931) saturation red light.
並列關鍵字
WPLED參考文獻
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