Polymer Light-Emitting Energy-Well Devices Using Single-Ion Conductors

Dramatically improved luminance and quantum efficiency of electroluminescent devices is achieved by packing the emissive conjugated polymer between thin layers of a single-cation and a single-anion conductor. These layers, both consisting of charged polyurethanes, exhibit high ionic space charges near the electrodes, and afford excellent charge-injection as well as a charge-blocking properties. This results in balanced injection and confinement of electron–hole pairs, and, hence, superior quantum efficiency.