INQUIMAE   12526
INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
artículos
Título:
Dynamics of Ion Exchange between Self-Assembled Redox Polyelectrolyte Multi-layer modified Electyrode and Liquid Electrolyte
Autor/es:
DORIS GRUMELLI; FERNANDO GARAY; CESAR BARBERO; ERNESTO JULIO CALVO
Revista:
JOURNAL OF PHYSICAL CHEMISTRY B
Editorial:
American Chemical Society
Referencias:
Año: 2006 vol. 110 p. 15345 - 15352
ISSN:
1089-5647
Resumen:
A probe beam deflection (PBD) study of ion exchange between an electroactive polymer poly(allylamine)--
bipyridyl-pyridine osmium complex film and liquid electrolyte is reported. The PBD measurements were
made simultaneously to chronoamperometric oxidation-reduction cycles, to be able to detect kinetic effects
in the ion exchange. Layer-by-layer (LbL) self-assembled redox polyelectrolyte films with osmium bipyridyl
complex covalently attached to poly(allylamine) (PAH-Os) and poly(styrene sulfonate) (PSS) have been
built by alternate electrostatic adsorption from soluble polyelectrolytes. The ionic exchange during initial
conditioning of the film (break-in) undergoing oxidation-reduction cycles and recovery after equilibration
in the reduced state have shown an exchange of anions and cations with time lag between them. The effect
of the nature of cation on the ionic exchange has been investigated with dilute HCl, LiCl, NaCl, and CsCl
electrolytes. The ratio of anion to cation exchanged at the film-electrolyte interface has a strong dependence
on the nature of charge in the topmost layer, that is, when negatively charged PSS is the capping layer, a
larger proportion of cation exchange is observed. This demonstrates that the electrical potential distribution
at the redox polyelectrolyte multilayer (PEM)/electrolyte interface determines the ionic flux in response to
charge injection in the film.-pyridine osmium complex film and liquid electrolyte is reported. The PBD measurements were
made simultaneously to chronoamperometric oxidation-reduction cycles, to be able to detect kinetic effects
in the ion exchange. Layer-by-layer (LbL) self-assembled redox polyelectrolyte films with osmium bipyridyl
complex covalently attached to poly(allylamine) (PAH-Os) and poly(styrene sulfonate) (PSS) have been
built by alternate electrostatic adsorption from soluble polyelectrolytes. The ionic exchange during initial
conditioning of the film (break-in) undergoing oxidation-reduction cycles and recovery after equilibration
in the reduced state have shown an exchange of anions and cations with time lag between them. The effect
of the nature of cation on the ionic exchange has been investigated with dilute HCl, LiCl, NaCl, and CsCl
electrolytes. The ratio of anion to cation exchanged at the film-electrolyte interface has a strong dependence
on the nature of charge in the topmost layer, that is, when negatively charged PSS is the capping layer, a
larger proportion of cation exchange is observed. This demonstrates that the electrical potential distribution
at the redox polyelectrolyte multilayer (PEM)/electrolyte interface determines the ionic flux in response to
charge injection in the film.-reduction cycles, to be able to detect kinetic effects
in the ion exchange. Layer-by-layer (LbL) self-assembled redox polyelectrolyte films with osmium bipyridyl
complex covalently attached to poly(allylamine) (PAH-Os) and poly(styrene sulfonate) (PSS) have been
built by alternate electrostatic adsorption from soluble polyelectrolytes. The ionic exchange during initial
conditioning of the film (break-in) undergoing oxidation-reduction cycles and recovery after equilibration
in the reduced state have shown an exchange of anions and cations with time lag between them. The effect
of the nature of cation on the ionic exchange has been investigated with dilute HCl, LiCl, NaCl, and CsCl
electrolytes. The ratio of anion to cation exchanged at the film-electrolyte interface has a strong dependence
on the nature of charge in the topmost layer, that is, when negatively charged PSS is the capping layer, a
larger proportion of cation exchange is observed. This demonstrates that the electrical potential distribution
at the redox polyelectrolyte multilayer (PEM)/electrolyte interface determines the ionic flux in response to
charge injection in the film.-Os) and poly(styrene sulfonate) (PSS) have been
built by alternate electrostatic adsorption from soluble polyelectrolytes. The ionic exchange during initial
conditioning of the film (break-in) undergoing oxidation-reduction cycles and recovery after equilibration
in the reduced state have shown an exchange of anions and cations with time lag between them. The effect
of the nature of cation on the ionic exchange has been investigated with dilute HCl, LiCl, NaCl, and CsCl
electrolytes. The ratio of anion to cation exchanged at the film-electrolyte interface has a strong dependence
on the nature of charge in the topmost layer, that is, when negatively charged PSS is the capping layer, a
larger proportion of cation exchange is observed. This demonstrates that the electrical potential distribution
at the redox polyelectrolyte multilayer (PEM)/electrolyte interface determines the ionic flux in response to
charge injection in the film.-reduction cycles and recovery after equilibration
in the reduced state have shown an exchange of anions and cations with time lag between them. The effect
of the nature of cation on the ionic exchange has been investigated with dilute HCl, LiCl, NaCl, and CsCl
electrolytes. The ratio of anion to cation exchanged at the film-electrolyte interface has a strong dependence
on the nature of charge in the topmost layer, that is, when negatively charged PSS is the capping layer, a
larger proportion of cation exchange is observed. This demonstrates that the electrical potential distribution
at the redox polyelectrolyte multilayer (PEM)/electrolyte interface determines the ionic flux in response to
charge injection in the film.-electrolyte interface has a strong dependence
on the nature of charge in the topmost layer, that is, when negatively charged PSS is the capping layer, a
larger proportion of cation exchange is observed. This demonstrates that the electrical potential distribution
at the redox polyelectrolyte multilayer (PEM)/electrolyte interface determines the ionic flux in response to
charge injection in the film.