Jy. Lim et al., A STUDY ON ION TRANSPORTS AND GROWTH OF CONDUCTING POLYPYRROLE WITH ELECTROCHEMICAL QUARTZ-CRYSTAL MICROBALANCE, Synthetic metals, 69(1-3), 1995, pp. 451-454
Growth of polypyrrole and ion exchange processes in the polypyrrole we
re investigated by an electrochemical quartz crystal microbalance for
various electrolytes. The polymer was deposited potentiodynamically or
potentiostatically on a gold film electrode. The mass change associat
ed with insertion and expulsion of ions in the polymer matrix with suc
cessive potential scans at the electrode and during the growth of the
polymer were monitored in situ. The observation supports that insertio
n of anions ink, polymer matrix in CH3CN occurs for anodic polarizatio
n and expulsion of the same ion for cathodic polarizaiton. However, ch
arge compensation occurs also by cations in aqueous electrolyte even w
hen the polymer is composed of small dopant anions. Also, it is found
that growth of polymer is much faster and induction period is much sho
rter in H2O than in CH3CN.