Advanced Functional Materials, Vol.20, No.11, 1812-1820, 2010
Positively Charged Iridium(III) Triazole Derivatives as Blue Emitters for Light-Emitting Electrochemical Cells
Cationic blue-emitting complexes with (2,4-difluoro)phenylpyridine and different 1,2,3-triazole ligands are synthesized With different counterions. The influence of the substituents on the triazole ligand is investigated as well as the influence of the counterions:The substituents do not change the emission energy but, in some cases, slightly the excited-state lifetimes and the emission quantum yields. The excited state lifetimes, in apolar solvents are slightly dependent on the nature of the counterion. A crystal structure of one of the compounds confirms the geometry and symmetry postulated on the basis of the other spectroscopic data Light-emitting electrochemical cell devices are prepared and the recorded emission is the bluest with the fastest response time ever reported for iridium complexes.