Ionic Dissociation Effects in Light Emitting Electrochemical Cells

The paper describes theoretically the ionic dissociation equilibrium which takes place in operating light-emitting electrochemical cells (LECs, based on a previously developed model. The model can be useful for understanding the behaviour of LECs: it is proposed that the ionic equilibrium may be related to the amount of residual solvent which is present in the film, both simulations and experiment showing that a decrease in the concentration of residual solvent leads to much longer response-times and lower currents. The slow response times may thus be due to two factors: very low dissociation equilibrium constant and very slow ion movement.