A wet and dry processable phosphorescent green dye based organic light-emitting diodes

Abstract

Electroluminescence-efficiency green emitter with both wet- and dry-process feasibility is highly desirable to realize cost-effective large roll-to-roll manufacturing and high performance products. We demonstrate here a wet- and dry-process feasible green bis[5-methyl-8-trifluoromethyl-5H-benzo(c)(1,5)naphthyridin-6-one]iridium(picolinate) containing organic light-emitting diode device with an efficacy roll-up character between 100 and 1000 cd/m2. The newly synthesized iridium complex exhibits a relatively short excited-state lifetime (0.39 μs) and a high quantum yield of 74%, both which warrant this complex to be a highly electroluminescence active candidate. The wet processed device using a 3,5-di(9H-carbazol-9-yl) tetraphenylsilane host, for example, shows a 52 lm/W with an 18% external quantum efficiency (EQE) at 100 cd/m2, which increases to 61 lm/W with a 23% EQE at 1000 cd/m2. For the dry-processed device using a 4,4-bis(carbazol-9-yl)biphenyl host, it is 59 lm/W with a 25% EQE at 1000 cd/m2.