Mesoscopic modelling of charge evolution in conducting polymers

Abstract

We address here some of the issues relating to conducting polymer based devices. We examine the effects of polymer disorder on charge injection, transport, trapping and recombination in light-emitting diodes (LEDs) using a mesoscopic model which includes specific realizations of the electroluminescent polymer network. A key point of this model is to consider both the intermolecular and the interdomain charge carrier transport which are strongly influenced by structural polymer disorder. Simulations of bipolar charge evolution (electrons and holes) through a polydiacetylene (PDA) film, which are injected in the polymer layer from the appropriated electrodes, have been used to give some insights to the issue concerning the fraction of polymer molecules contributing to the conduction process as well as to light emission. The effect of charge traps, such as cross-links, on space charge and recombination is also discussed.