Research Center of Advanced Materials Science and Technology and MOE Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology , Taiyuan 030024, P. R. China.
Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications (NUPT) , Nanjing 210023, P. R. China.
ACS Appl Mater Interfaces. 2017 Nov 1;9(43):37873-37882. doi: 10.1021/acsami.7b10300. Epub 2017 Oct 17.
Two highly efficient red neutral iridium(III) complexes, Ir1 and Ir2, were rationally designed and synthesized by selecting two pyridylimidazole derivatives as the ancillary ligands. Both Ir1 and Ir2 show nearly the same photoluminescence emission with the maximum peak at 595 nm (shoulder band at about 638 nm) and achieve high solution quantum yields of up to 0.47 for Ir1 and 0.57 for Ir2. Employing Ir1 and Ir2 as emitters, the fabricated red organic light-emitting diodes (OLEDs) show outstanding performance with the maximum external quantum efficiency (EQE), current efficiency (CE), and power efficiency (PE) of 20.98%, 33.04 cd/A, and 33.08 lm/W for the Ir1-based device and 22.15%, 36.89 cd/A, and 35.85 lm/W for the Ir2-based device, respectively. Furthermore, using Ir2 as red emitter, a trichromatic hybrid white OLED, showing good warm white emission with low correlated color temperature of <2200 K under the voltage of 4-6 V, was fabricated successfully. The white device also realizes excellent device efficiencies with the maximum EQE, CE, and PE reaching 22.74%, 44.77 cd/A, and 46.89 lm/W, respectively. Such high electroluminescence performance for red and white OLEDs indicates that Ir1 and Ir2 as efficient red phosphors have great potential for future OLED displays and lightings applications.
两个高效的红色中性铱(III)配合物 Ir1 和 Ir2 通过选择两个吡啶基咪唑衍生物作为辅助配体被合理设计和合成。Ir1 和 Ir2 都显示出几乎相同的光致发光发射，最大峰值在 595nm（肩峰约在 638nm），并实现了高达 0.47 的 Ir1 和 0.57 的 Ir2 的高溶液量子产率。使用 Ir1 和 Ir2 作为发射器，所制造的红色有机发光二极管（OLED）表现出出色的性能，Ir1 基器件的最大外量子效率（EQE）、电流效率（CE）和功率效率（PE）分别为 20.98%、33.04 cd/A 和 33.08 lm/W，Ir2 基器件分别为 22.15%、36.89 cd/A 和 35.85 lm/W。此外，使用 Ir2 作为红色发射器，成功制造了一种三基色混合白色 OLED，在 4-6V 的电压下，其具有良好的暖白色发射，相关色温<2200K。该白色器件还实现了出色的器件效率，最大 EQE、CE 和 PE 分别达到 22.74%、44.77 cd/A 和 46.89 lm/W。红色和白色 OLED 的如此高的电致发光性能表明，Ir1 和 Ir2 作为高效红色磷光体在未来的 OLED 显示器和照明应用中具有巨大的潜力。
