離子性銥金屬錯合物高效率飽和紅光固態發光電化學元件

Efficient and saturated red light-emitting electrochemical cells based on cationic iridium complexes

余光祥(Guang-Xiang Yu)

指導教授 ： 蘇海清

國立交通大學/光電學院/照明與能源光電研究所/碩士(2019年)

摘要

近年來固態有機發光電化學元件具有簡單的元件構造、使用溶液製程元件節省在製程上的時間成本、低操作電壓、使用惰性陰極金屬、以及對於大面積可撓曲基板的高相容性等優點受到學界關注。這些優點對於固態有機發光電化學元件應用在顯示器上是具有潛力的，對於顯示器中高飽和紅光(650 nm)更是扮演重要的角色，高飽和紅光有助於擴大色域範圍使顯示器色彩呈現的精準度提升，帶給觀看者較華麗且飽滿的色彩風格。在過去文獻中銥離子紅光電化學元件常有效率不佳或者是不夠飽和之情況，本實驗使用一系列紅光銥離子金屬錯合物，進行紅光電化學元件製作與量測，這些元件光色都超過National Television System Committee (NTSC)標準紅光色座標頂點(0.67, 0.33)，元件外部量子效率最高可達7.4%，高於其他已發表的類似光色元件，利用主客體元件可以進一步提升元件外部量子效率至9.4%。此外，通過擬合電致發光頻譜與微共振腔效應下的模擬光譜能探討複合區中主客體有機發光電化學元件的載子平衡，證實調整客體摻雜濃度可以改善載子平衡以提升元件效率。

關鍵字

離子性銥金屬錯合物 ； 飽和紅光 ； 發光電化學元件

並列摘要

Solid-state light-emitting electrochemical cells (LECs) show several advantages such as low-voltage operation, simpler solution-processable, compatibility with inert metal electrodes and large-area flexible substrates. These promising properties ensure their potential application in low-cost displays. Saturated red light sources, which exhibit emission peak approaching 650 nm, are essential for full-color displays since they can generate large color gamut. The display with wider color gamut bring a more gorgeous and full color style to viewers. Several works on saturated red LECs based on iTMCs have been reported. However, most of these works exhibit low or moderate device efficiencies. In this work, we propose several novel red-emitting cationic iridium complexes and test their EL characteristics in LECs. The Commission internationale de l'éclairage (CIE) 1931 coordinates of the red spectra from the LECs based on these complexes are all beyond the National Television System Committee (NTSC) red standard point (0.67, 0.33). The maximal external quantum efficiency (EQE) reaches 7.4%. To further increase the device efficiency of the saturated red LECs, the host-guest strategy is employed. The maximal EQE of the host-guest LECs reach 9.4%. Extracting the recombination zone by fitting the measured EL spectrum and the simulated EL spectrum based on microcavity effect is performed to study the carrier balance of the host-guest LECs. Adjusting guest doping concentration can improve carrier balance and consequently enhances device efficiency of the host-guest red LECs

並列關鍵字

cationic iridium complexes ； saturated red ； light-emitting electrochemical

參考文獻

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