Improved Stability of Solid State Light Emitting Electrochemical Cells Consisting of Ruthenium and Iridium Complexes

Abstract

Two charged organometallic complexes containing bulky hydrophobic ligands based on ruthenium (II) and iridium (III) were synthesized and their performance in solid state light emitting electrochemical cells is described. The complexes were chosen as due to their large ligands a diminished susceptibility towards the formation of destructive complexes during device operation is expected. The LEC device performances reveal the longest living devices reported so far under dc bias. Quantum chemical calculations confirm that the major effect of the bulky diphenylphenanthroline ligands is of steric origin and not related with changes in the molecular electronic structure of the complexes.

A trip in the nonlinear optical properties of iridium complexes

“…In 2006-2007, a large number of heteroleptic iridium(III) complexes bearing two cyclometalated phenylpyridines and an ancillary diimine ligand such as bipyridine [64][65] or phenanthroline [66][67][68] were reported to act as emitters in electroluminescent devices. DFT calculations on this family of phosphorescent iridium(III) compounds showed that the HOMO is mostly an antibonding combination of Ir (t 2g ) orbitals and π orbitals of the cyclometalated ligand whereas the LUMO is localized on the π* antibonding orbitals of the ancillary ligand [64][65][66][67][68].…”