MODELING OF GROWTH-MORPHOLOGY OF UNDERPOTENTIAL ELECTROPOLYMERIZATIONOF PYRROLE ON GRAPHITE

Recent work has revealed that nanostructured polypyrrole can be prepar ed electrochemically by an underpotential process on graphite. Potenti al step experiments using this process are characterized by geometrica lly increasing current. We have preferred to view data from the experi ments in log-log format, plotting current vs. total charge passed duri ng the process. This report is an effort to model the relationship bet ween the morphology of polymer growth and the limiting slopes found in the log-log plots. We find that, regardless of the growth morphology, shape- (or aspect-) preserving growth in n dimensions is characterize d by a slope of n-1/n.