有機發光二極體(Organic-Light Emitting Diodes, OLED)，其優勢為高對比、全彩化、可撓、自發光等，已成為現今顯示器的主流；製作高效率元件有益壽命的提升，是許多研究團隊爭相追逐的目標。
以往在製作高效率元件時，受限於單重態及三重態的激子在收集上的困難，使效率無法顯著的提升；除了材料本身的限制，在製程中，激子的產生和電荷平衡，也是高效率元件的關鍵因素，改善激子的產生，在於分子間優異的電荷轉移與適當的能階配置，使得電子-電洞複合產生有效激子。
本研究採用供體(Donor)及受體(Acceptor)的分開設計，使兩材料間的電子雲完全分開，形成激發複合體(Exciplex)，利用電洞傳輸材料3,6-Bis(N-carbazolyl)-N-phenylcarbazole（BCC-36）和電子傳輸材料2,4,6-Tris[3-(diphenylphosphinyl)phenyl]-1,3,5-triazine（PO-T2T），有效的形成激發複合體，不僅打破材料本身單重態及三重態最大內部量子效率的限制，其電子-電洞也能有效結合，大大提升元件表現，其光激發光譜的紅移證實了激發複合體的形成，利用時間解析光激發光譜(Time-Resolved Photoluminescence，TRPL)的放光時間延長(1.8微秒)，代表了激發複合體擁有極佳的熱活化延遲螢光(Thermally Activated Delayed Fluorescence, TADF)機制。
透過良好的激發複合體形成，研製出一高效率元件，在亮度100 cd/m2下，其能量效率為27 lm/W，外部量子效率為17％，電流效率為40 cd/A，最大外部量子效率可達20％。
此一高效率之激發複合體，可歸因於(1) 供體和受體材料均具有高三重態能階，形成激發複合體之單重態及三重態能階差小；(2) 優異的電荷傳輸能力，平衡電子及電洞的結合，有效的形成激發複合體激子；(3)提高供體材料最高分子填滿軌域(HOMO)及受體材料最低分子未填滿軌域(LUMO)之間的能量差異，以利電子電洞結合；(4) 良好的元件結構設計，以減少電洞及電子注入時所需跨過的能障。

Organic-Light Emitting Diodes (OLED), which have the advantages of high contrast, full color, flexible, self-illuminating, etc., Because of the above advantages, OLED have become the mainstream of today's displays; Making high-efficiency devices are beneficial to lifetime,Which is the goal that many research teams are chasing.
In the past, when manufacturing high-efficiency devices, it was limited by the difficulty of collecting singlet and triplet excitons, so that the efficiency could not be significantly improved; in addition to the limitation of the material itself, exciton generation and charge balance are also the key factor for high-efficiency devices. The improvement of exciton generation due to the excellent charge transfer between molecules and the proper energy level configuration, so that electron-hole can recombin produces effective excitons.
In this study, a separate design of donor (Donor) and acceptor (Acceptor) was used to completely separate the electron clouds between the two materials to form an exciplex. By using hole transport material 3,6-Bis (N-carbazolyl)-N-phenylcarbazole (BCC-36) and the electron transporting material 2,4,6-Tris[3-(diphenylphosphinyl)phenyl]-1,3,5-triazine(PO-T2T), effectively forming an exciplex, Not only breaks the limitation of the singlet state and the triplet state of the material, but also the electron-holes can be effectively combined to greatly enhance the performance of the device. The red shift of the photoexcitation spectrum confirms the formation of the exciplex, and the (Time-Resolved Photoluminescence，TRPL) has a longer exposure time, which represents an excellent thermal activation delayed retardation (TADF) mechanism for the exciplex.
Through the formation of a good exciplex, a high-efficiency device was developed with a power efficiency of 27 lm/W, an external quantum efficiency of 17%, a current efficiency of 40 cd/A at a luminance of 100 cd/m2, and a maximum external quantum efficiency can reach 20%.
This high-efficiency exciplex can be attributed to (1) both the donor and acceptor materials have high triplet energy levels, and the small energy level between singlet and triplet; (2) excellent Charge transfer capability, balancing the combination of electrons and holes, effectively forming excitons; (3) increasing the highest molecular filled orbital (HOMO) of the donor material and the lowest molecular unfilled orbital (LUMO) of the acceptor material ,To benefit the electron-hole recombination; (4) Good device structure design to reduce the energy barriers required for hole and electron injection.

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