Key Ionic Electrolytes for Highly Self‐Stable Light‐Emitting Electrochemical Cells Based on Ir(III) Complexes

Self-stability in light-emitting electrochemical cells (LECs) based on Ir(III) ionic transition metal complexes (Ir-iTMC) has been long overlooked. Herein, it is demonstrated that the nature of the active layer blending an archetype Ir-iTMC as emitter and ionic electrolytes—ionic liquid (IL) or ionic polyelectrolyte (IP)—is paramount for the storage and mechanical stability of rigid/flexible LECs. Strikingly, devices with ionic polyelectrolytes (IPs) stand out compared to those with traditional configurations with or without ILs. They exhibit i) superior brightness and efficiencies in rigid/flexible devices due to the higher photoluminescence quantum yield, ii) the best performance at pulsed current driving mode under inert/ambient operation conditions due to a slower growth of the doped regions, iii) enhanced device stabilities upon ambient/inert storage, resulting in