Yellow organic light-emitting diodes based on phosphorescent iridium(III) pyrazine complexes: Fine tuning of emission color

The synthesis and luminescence of a series of new iridium pyrazine complexes were investigated. The phosphorescent peak wavelength can be fine-tuned in yellow color range of 553–588 nm. Complexes 4 and 6 were used as representative examples for fabrication of multilayered OLEDs. The two OLEDs all exhibited high efficiency. The devices based on complex 4 exhibited an external quantum efficiency of 4.6% (power efficiency 9.7l m/W) and a maximum brightness of 32 700 cd/m2. The device also showed high color purity with an emission maximum at 561 nm and Commission Internationale de l’Eclairage (CIE) coordinates of (x = 0.45, y = 0.54).

A series of new phosphorescent iridium(III) pyrazine complex has been successfully synthesized. We aim to fine tune the yellow color emission in range of 553–588 nm by using appropriate ancillary and cyclometalating ligands containing different substituent groups. The results suggest that the strategies for tuning emission color used in phenyl pyridine based organometallic complexes are also suitable to phenyl pyrazine based Ir(III) complexes.Figure optionsDownload as PowerPoint slide