Synthesis and luminescent properties of Ir complexes with fluorine substituted phenylpyridine derivative ligands

Two phosphorescent iridium(III) complexes Ir(DFPP)2(acac) and Ir(DFPP)2(pic) (DFPP, 2-(2,4-difluorodephenyl)-3-phenylpyridine; acac, acetylacetone; pic, 2-picolinic acid) were synthesized. The complexes have strong phosphorescent characters. The organic light emitting devices (OLEDs) based on these complexes with the configuration of ITO/NPB (40 nm)/Ir complex: CBP (7%, 30 nm)/BCP (15 nm)/Alq (30 nm)/LiF (1 nm)/Al (100 nm) were fabricated. The device based on Ir(DFPP)2(acac) emits green color with a maximum external quantum efficiency of 4.14%, a brightness of 28,786 cd m−2; and the device based on Ir(DFPP)2(pic) emits cyan color with a maximum external quantum efficiency of 3.05%, a brightness of 24,220 cd m−2.