Abstract:
Modification of electrode matrices with conducting copolymer was attempted. The
electrodes thus modified were examined for their performance in carrying out
some standard electrochemical redox processes on thelf surfaces .
PI electrode was modified with the films of
i) conducting polymers, viz., PANI, CH3-PANI, PABA and PP
Ii} conducting copolymers, viz., PANII CH3-PANI, PANI/PP, PANI/PABA
iii) polymeric composites, viz" PANI/CH3-PANIISiO" PANI/PPI$I02
The film of conducting polymers, copolymers and the composites were prepared
by the simple one step electrochemical means. Corresponding monomer(s),
inorganics were kept III electrolytic solutions and deposited a polymeric film onl0
the PI substrates either by sweeping the polentials or by constant potential mode.
The film thus grown onto the Pt surface were free-standing depending on lhe
thickness of the deposit grown.
The modifier matrices were characterized by a wide range of experimental
techniques including UV-Vis and IR spectroscopy, d c. conductance and
scanning electron microscopy. IR spectral analysis Yielded characteristic bands
confirming the presence of polymeric and inorganic components. UV-Vis optical
spectra of the samples showed strong absorption maxima in ultraviolet region
and another band in the VISible region that are attnbutable for conductive
polymeric component The electrical conductivity of the samples was measured
in their compressed solid state The electrode matrices that are synthesized in
this study are found to be fairly conductive and their conductiVity falls in the range
of conventional semiconductors The surface morphology of the modified
electrodes was examined. The matrices showed diSSimilar surface morphology
from granular to fibril. The dissimilar surface morphology showed different
electrode activity of the matrices.
The electrode matrices thus modified were found to be electroactive both in
aqueous and non-aqueous solvents The polymeric electrodes in the appropnate
electrlytlc media exhibited doping-dedoping phenomenon corresponding to the
polymeric oxidation-reduction processes, respectively, ThiS result indicates Ule
charging-discharging capacities of modified electrodes,
The electrolytic matrices were then used as modified electrode. The redox
processes Fe2' --+ Fe" + e' and H20 --+ 0 + 2H' + 2e' were performed on their
surfaces The modified electrodes thus prepared in this study were found to be
capable of performing the redox processes effiCiently. The effects of solvent and
film thickness on the performance of the modified electrodes were also
investigated. The presenl study clearly revealed that conducting copolymer
modified electrode could be a good replacement lor the costly noble Pt eleclrode
In terms of cost, availability and ease of techniques for preparation and
application in a real system.
