開發新型可熱交聯的電洞傳輸及碳60材料於高分子發光二極體及太陽能電池之應用

Abstract

溶液製程的方法已被廣泛的用於製造多層結構的高分子發光二極體和太陽能電池 之元件。 然而，溶液製程所遭遇的最大挑戰就是剛形成的底層常會被隨後一層所使用 的溶劑所侵蝕。 目前所浮現的最好的辦法來解決這個問題就是使旋轉塗佈後的材料進 行交聯反應以產生對有機溶劑不再可溶的狀態。 在本研究中，我們將利用我們的專長 合理的設計一系列的分子來達到電洞傳輸材料各種所必備的要求，如高的熱穩定性、電 化學的可逆性、可調節的HOMO 能階、好的電洞遷移率以及電子阻檔力。 Diels-Alder 和1.3 dipolar cycloaddition 反應將會被利用並且導入電洞傳輸材料做為快速又有效率的 交聯反應。 其目的是要有效的大幅降低交聯的反應溫度與時間。 這種聰明控制電洞傳 輸材料交聯反應的策略將對元件工程將帶來極大的好處，如較簡易的製成、較低的成 本、可引入對熱敏感的PEDOT:PSS 以及加入P-doping 的電子受體來增加電洞傳輸層的導 電度。 這些新開發的熱交聯電洞傳輸材料將有很大的潛力來實現高效率的藍-綠-紅乃 至於白光高分子發光二極體或是量子點的發光二極體。 具有反式結構的有機太陽能電池元件比起傳統的結構已被證實擁有較佳的穩定性。 但是能量轉換效率仍然需要被同時的有效提升。 本計劃的第二部分是設計並開發可熱 交聯的富勒烯(碳60)，並且可用於反式結構的有機太陽能電池中的電子選擇層。 這些 厚度可調節的碳60 層可以增加與含PCBM 吸光層的相容性，並且有機會可取代常做為電 子傳輸層的金屬氧化物以達到較高的元件表現，同時也將具有容易製作及較好的穩定 度。 本計劃共結合材料設計，大分子的結構，反應的控制，以及層與層之間的元件工 程。 我們預期成功的實現本計劃將會對未來高分子發光二極體和太陽能電池的應用與 前景帶來極大的好處及影響。

Solution-processed approach has been widely used to fabricate muiltlayer PLEDs and solar cell devices. However, one of the major challenges for solution processing is the erosion of the bottom layer caused by the solvent used in the subsequent step. Spin-coated materials which can be crosslinked thereafter to form an insoluble network have emerged as the best way to solve this problem. In this proposal, we will employ our expertise to rationally design a new series of hole-transporting materials to fulfill many prerequisites such as high thermal stability, electrochemical reversibility, tunable HOMO levels, good hole-mobility and electron-block ability. Well-defined Diels-Alder or 1.3 dipolar cycloaddition “click chemistry” will be utilized and incorporated into these HTM systems as the efficient crosslinking reactions in bulk in order to significantly reduce the curing temperature. This strategy of smartly-controlled crosslinking reactions in HTM systems will make great benefits for device engineering including easier fabrication, low production cost, insertion of thermal sensitive layer PEDOT:PSS and incorporation of p-doping acceptor materials to improve the conductivity. The newly developed thermally crosslinkable materials will show great potentials in realizing the high performance of red-green-blue-(RGB)-emitting PLEDs as well as white and quantum dot-based PLEDs. Inverted solar cell has been demonstrated to have excellent device stability as compared to conventional structure. However, the power conversion efficiency of the device still needs to be improved simultaneously. The second part of this proposal is to design and develop thermally crosslinkable fullerenes which can be processed as the electron selective layer for inverted solar cells. This thickness-tunable layer can improve the compatibility with active layer containing PCBM and may potentially replace the function of metal oxide, resulting in higher device performance with ease fabrication and better stability. This research is an integration of material design, macromolecular architecture, reaction controlling and device interface engineering. It is expected that the successful realization of this proposal will bring significant impact on the promising and profitable application of polymer light-emitting and solar cell devices.