Luo Dian, Hsieh Chung-Tsung, Wang Yen-Po, Chuang Thomas C, Chang Hsin-Hua, Chang Chih-Hao
Department of Electrical Engineering, Yuan Ze University Chung-Li Taiwan 32003
Department of Information Science and Technology, Vanung University Chung-Li Taiwan 32061.
RSC Adv. 2018 Aug 30;8(53):30582-30588. doi: 10.1039/c8ra04986f. eCollection 2018 Aug 24.
An exciplex could be formed by blending a selected hole-transporting material (HTM)/electron-transporting material (ETM) pair, and the corresponding energy band gap is roughly determined by the energy difference between the lowest unoccupied molecular orbital (LUMO) of the ETM and the highest occupied molecular orbital (HOMO) of the HTM. In this study, three HTM/ETM combinations are adopted to generate blue, green, and red exciplexes, allowing us to design precise device architectures for the fabrication of exciplex-based white OLEDs (WOLEDs) with daylight-like emissions. The CIE coordinates of this WOLED varied close to the Planckian locus as the biases increase, with a high color rendering index of about 96. This high performance suggests this exciplex-based WOLED can provide high-quality white-light illumination. Photoluminance and lifetime measurements of the exciplex behavior of the HTM/ETM combinations indicate that the HTM and ETM selected should possess higher triplet energy bandgaps than those of their corresponding exciplex to avoid energy loss.
通过混合选定的空穴传输材料（HTM）/电子传输材料（ETM）对可以形成激基复合物，并且相应的能带隙大致由ETM的最低未占据分子轨道（LUMO）与HTM的最高占据分子轨道（HOMO）之间的能量差决定。在本研究中，采用三种HTM/ETM组合来产生蓝色、绿色和红色激基复合物，这使我们能够设计精确的器件结构，以制造具有类似日光发射的基于激基复合物的白色有机发光二极管（WOLED）。随着偏压增加，该WOLED的CIE坐标接近普朗克轨迹变化，显色指数约为96。这种高性能表明这种基于激基复合物的WOLED可以提供高质量的白光照明。对HTM/ETM组合的激基复合物行为进行的光致发光和寿命测量表明，所选择的HTM和ETM应具有比其相应激基复合物更高的三重态能带隙，以避免能量损失。
