Electrografting and electropolymerization of nanoarrays of PANI filaments through silica mesochannels
Résumé
Vertically aligned mesoporous silica films electrogenerated on indium-tin oxide (ITO) electrodes are used as hard
templates for the electrochemical growth of polyaniline (PANI) nanofilaments. To ensure proper adhesion of
PANI to the underlying ITO surface, aniline moieties are first covalently attached to the bottom of mesochannels
via electrografting of aminophenyl diazonium cations, serving in a second step as precursors for PANI growth by
electropolymerization of aniline through the silica mesochannels. This was achieved by cyclic voltammetry or
potentiostatically at an applied potential of +0.85 V (vs. Ag/AgCl), the latter offering a better control of the
nanofilaments length by tuning the electropolymerization time. PANI wires remain attached to ITO after etching
of the silica membrane, confirming the importance of initial electrografting. Although PANI nanofilaments in the
silica membrane remain electroactive, enhanced peak currents were observed after silica removal as PANI
nanofilaments offer a larger effective surface area to the electrolyte solution.
Origine | Publication financée par une institution |
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