Solubilised bright blue-emitting iridium complexes for solution processed OLEDs

摘要

Combining a sterically bulky, electron-deficient 2-(2,4-difluorophenyl)-4-(2,4,6- trimethylphenyl)pyridine (dFMesppy) cyclometalating CN ligand with an electron rich, highly rigidified 1,1’-(α,α’--xylylene)-2,2’-biimidazole (-xylbiim) NN ligand gives an iridium complex, [Ir(dFMesppy)(-Xylbiim)](PF6), that achieves extraordinarily bright blue emission (Φ = 90%; λ = 459 nm in MeCN) for a cationic iridium complex. This complex is compared with two reference complexes bearing 4,4’-di--butyl-2,2’- bipyridine, and solution-processed organic light emitting diodes (OLEDs) have been fabricated from these materials.