- 學位論文
電激發藍色磷光元件之高能隙主體材料開發暨應用
High Energy-Gap Hosts for Blue Electrophosphorescent Devices
摘要
中文摘要 本論文包含三個部份，前二個部份報導利用新咔唑型分子和新二氫蒽衍生物作為藍色磷光主體材料的研究，在藍色元件上皆有很不錯的元件效率表現，而新咔唑型分子具有高三重態能隙2.95 eV，其中以DPIA-tBu和FIrpytz搭配的元件2-B效能表現，最大外部量子效率7.76 %，電流效率13.45 cd/A，功率4.52 lm/W，CIE座標(0.14, 0.24)；而新二氫蒽衍生物具有高單重態能隙4.4 eV，以TTA-OMe搭配FIrpytz的元件3-F為最佳，最大外部放光效率為5.69 %，電流效率9.85 cd/A，功率為4.67 lm/W，CIE(0.13, 0.23)，這兩個部份的元件相對於mCP的元件效率都有兩倍以上的改良。第三個部份主要是以雙三苯基矽烷衍生物作為藍色磷光主體材料的系統化研究，其中共有四個材料搭配FIrpytz具有很好的元件效能表現，效率最好的為BSB元件4-AD，EQE：10.50 %；mBST元件4-X，EQE：11.53 %；oBST元件4-AB，EQE：10.72 %和pBST-TM元件4-R，EQE：10.96 %。而其中BSB搭配FIrpytz的元件4-G，可以得到藍色磷光元件最好的效率，驅動電壓為5.1 V，最大外部放光效率為19.3 %，功率為16.8 lm/W，CIE座標(0.15, 0.32)，這個值已經接近元件外部放光效率的極限值20 %，是已知的藍色磷光元件中效率最好的。
並列摘要
Abstract This thesis includes three parts that involves design, synthesis and characterization of new host materials of blue phosphorescence OLED. In the first part, we have prepared DPIA derivatives having high triplet energy gap of 2.95 eV. The best performance of the DPIA-doping-FIrpytz-based devices 2-B shows maximum EQE of 7.76 %, current efficiency of 13.45 cd/A, and power efficiency of 4.52 lm/W with CIE coordinate(0.14, 0.24). In the second part, we have synthesized TTA derivatives having high singlet energy gap of 4.4 eV. Among the TTA-doping-FIrpytz-based devices, the device 3-F revealed maximum EQE of 7.76 %, current efficiency of 13.45 cd/A, and power efficiency of 4.52 lm/W with CIE coordinate of (0.14, 0.24). the above two devices showed efficiency twice that of the mCP based devices. In the third part, we demonstrate systematic study on BS derivatives being good hosts of blue phosphorescence OLED. There are four BS derivatives-doping-FIrpytz based deivces with excellent performance showed below: BSB-based device 4-AD, EQE=10.50 %; mBST-based device 4-X, EQE=11.53 %; oBST-based device 4-AB, EQE=10.72 %; pBST-TM-based 4-R, EQE=10.96 %. In particular, the use of FIrpytz as dopant, device 4-G of BSB as host and LiF/Al as cathode provides a remarkably efficient combination for blue electrophosphorescent device reaching a very high external quantum efficiency of 19.3% and a high power efficiency of 16.8 lm/W after electroluminescence starting at 5.1 V.