Effect of Thermal Annealing on Polymer Light-Emitting Diodes Utilizing Cationic Conjugated Polyelectrolytes as Electron Injection Layers

摘要

The effect of thermal annealing on the performance of polymer light-emitting diodes (PLEDs) with a cationic conjugated polyelectrolyte as an electron injection layer is investigated. Thermal annealing at 180 °C leads to the loss of ionic content via Hofmann elimination and, hence, increases the device turn-on voltage. The ability to reduce the ionic charge density opens opportunities to design experiments for disentangling the operating mechanism for the reduction of electron injection barriers in PLEDs.