Organic Electrode Reactions - Fundamentals and Applications of Organic Electrochemistry - page 172

potential to a working electrode for a long
period should be avoided since the product
polymer with extended π-conjugation is easily
oxidized compared to the corresponding
monomer.

The potential sweep and

potentiostatic methods require milder

polymerization conditions than the

galvanostatic method.

In the potential sweep method, polymerization
is carried out with CV analyzer. A working
electrode, a counter electrode and a reference
electrode are put together in an electrolytic cell
containing electrolyte and monomer. The
repeating potential sweep across the potential
range determined from the advanced CV
measurement produces product polymer film
on the working electrode and this
electron-transfer process can be monitored by
CV, as shown in Figure 5.19 , which shows
typical cyclic voltammograms of pyrrole during
electropolymerization. The first scan represents
the oxidation current of pyrrole monomer and
then polymerization proceeds at the surface of
the working electrode, resulting in an
irreversible voltammogram. In the course of
deposition of the product polypyrrole during
repeated scans, anodic and cathodic currents
derived from redox of polypyrrole at a lower
potential range gradually increase.