Temperature and Electric Field Dependent Electron Transport in Cationic and Anionic Conjugated Polyelectrolytes

The temperature and electric field dependence of electron mobilities in conjugated polyelectrolytes (CPEs) with structure variations of the ionic functionality and counterions were investigated to gain insight into the influence of these parameters on charge transport. Electron mobilities were determined by using electron-only diodes, and the temperature and electric field dependence were modeled with the Gaussian disorder model, the correlated Gaussian disorder model, and the polaronic correlated Gaussian disorder model for comparison. The transport characteristics were found to be dependent on the type of charge, as well as the choice of counterion, with the former baring a stronger influence on transport. Anionic CPEs are more susceptible to differences in the calculated energetic disorder than their cationic counterparts. Examination of cationic CPEs with different counterions show that, although the energetic disorder is similar, large differences in electron mobilities can be obtained. These observations provide useful structural handles to tailor and manipulate charge carrier mobilities.