An electron-transporting counter-anion, OXD-7-SO, 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 PF counter-anion, due to the facilitated electron-injection/transport and more balanced carrier recombination imparted by OXD-7-SO.
An electron‐transporting anion prepared by anchoring a sulfonate group onto an electron‐transporting molecule through a flexible alkyl chain and its use as the counter anion in a cationic iridium complex is reported. The flexible alkyl chain improves the solubility of the bulky anion in water or in polar organic solvents. The anion exhibits similar photophysical and electrochemical properties to the parent electron‐transporting molecule. Within the complex, the anion does not disturb the phosphorescence of the cation in the solid film. Solution‐processed small‐molecule organic light‐emitting diodes (OLEDs) using the complex as the dopant show superior performances over the reference device using the conventional complex with a PF6− counter anion. It is revealed that anchoring anionic groups to optoelectronically active molecules with flexible alkyl chains is a feasible approach to develop optoelectronically active anions for assembling ion pairs with advanced optoelectronic properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.