Organic light emitting devices based upon divalent osmium complexes. Part 1: design, synthesis, and characterization of osmium complexes

摘要

In this work we present the synthesis and characterization of several novel osmium complexes of the form [Os(N-N)_2L-L]~(2+) 2X~- designed for organic light emitting device (OLED) applications. In the complex notation N-N represents a derivative of 2, 2'-bipyridine or 1, 10-phenanthroline and L-L represents a strong π-acid arsine or phosphine ligand. The complexes feature ~3MLCT emission that ranges from 611-650 nm, which makes them suitable as an emission source for red OLEDs. Phosphorescent quantum yields as high as 45% and emission lifetimes as short as 400 nanoseconds have been reached.