A cationic iridium complex meets an electron-transporting counter-anion: enhanced performances of solution-processed phosphorescent light-emitting diodes.

An electron-transporting counter-anion, OXD-7-SO3 - , was developed for a blue-green-emitting cationic iridium complex, which showed superior device performance in solution-processed phosphorescent light-emitting diodes over its counterpart complex with a PF6 - counter-anion, due to the facilitated electron-injection/transport and more balanced carrier recombination imparted by OXD-7-SO3 - .