Supporting Information for Chronoamperometric Study of Conformational Relaxation in PPy(DBS)

The effect of the working electrode surface must be considered in this type of study, since it is thought to strongly influence the kinetics of relaxation [1]. The ESCR model was developed based on experimental data obtained from PPy films deposited on polished Pt. In those (anion-transporting) systems, nucleation was observed in the form of expanding cylinders that coalesced over time (visible via the electrochromism of these polymers). The ESCR model thus included the effects of nucleation and coalescence. This is in contrast to the uniform color changes during switching in our study, which employed as substrates thermally evaporated Au on highly polished Si (see Figure 1-SI): no nucleation occurred (or, conversely, nucleation occurred in so many places at once that it could not be observed). So, while our results agree with the ESCR model, it should be noted that future work should adapt the model to include uniform front propagation. Future models should also include the role of drift on ion transport.