Ion motion in conjugated polyelectrolyte electron transporting layers

The time responses of polymer light-emitting diodes (PLEDs) incorporating conjugated polyelectrolyte electron transport layers (ETLs) are reported. Longer times are required with thicker ETL layers and with smaller applied voltages. These observations are consistent with a reduction of the electron injection barrier that depends on the ion motion in the ETL. The devices are a hybrid between PLEDs and light-emitting electrochemical cells.