INVESTIGADORES
AZZARONI Omar
artículos
Título:
Self-Assembled Redox Polyelectrolyte-Surfactant Complexes:Nanostructure and Electron Transfer Characteristics of Supramolecular Films with Built-In Electroactive Chemical Functions
Autor/es:
M.L. CORTEZ; G.A. GONZÁLEZ; M. CEOLÍN; O. AZZARONI; F. BATTAGLINI
Revista:
ELECTROCHIMICA ACTA
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 2014 vol. 118 p. 124 - 129
ISSN:
0013-4686
Resumen:
The mesostructural and electrochemical characterization of a
redox-active polyelectrolyte-surfactant complex formed by polyallylamine
tagged with an osmium complex and dodecylsulfate is presented. X-ray
reflectivity (XRR), grazing-incidence small-angle X-ray scattering
(GISAXS), X-ray photoelectron spectroscopy (XPS), contact angle
goniometry (CA) and cyclic voltammetry (CV), including the numerical
simulation of the voltammetric response, were employed to analyze the
structure, stability and the electrochemical response of these
supramolecular films. In contrast to redox-active polyelectrolyte
multilayers (PEMs), the self-assembled system presented here shows a
mesoscopic order yielding a film of layered structure very stable to an
aqueous environment where the hydrophilic moieties (amino and sulfate
groups) are not exposed to the solution since a contact angle of 95° is
observed upon exposure to water. However, the film shows a self-exchange
electron transfer mechanism with an apparent diffusion coefficient of
2 × 10−9 cm2 s−1 for a film of 300 nm
of thickness. This behavior shows that the film exposed to an aqueous
solution undergoes a fast electron transfer process to/from the
electrode surface and ions to/from the electrolyte solution.