A Fourier Transform Infrared Reflection-Absorption Spectroscopy Study of Redox Polyelectrolyte Films

C. BONAZZOLA,; ERNESTO JULIO CALVO; F.C. NART,

LANGMUIR

Año: 2003 p. 5279 - 5286

0743-7463

Self-assembled polyelectrolyte multilayer films comprised of poly(allylamine) derivatized with an Os- (bpy)2ClPyCH- complex (PAH-Os), and poly(vinylsulfonate), PVS, or poly(styrensulfonate), PSS, have been studied by Fourier transform infrared reflection-absorption spectroscopy. The infrared absorbances of the characteristicSO32ClPyCH- complex (PAH-Os), and poly(vinylsulfonate), PVS, or poly(styrensulfonate), PSS, have been studied by Fourier transform infrared reflection-absorption spectroscopy. The infrared absorbances of the characteristicSO3-absorption spectroscopy. The infrared absorbances of the characteristicSO33 -,CH2,NH3,CH2,NH3 +, and aromatic bipyridine and pyridine groups have been characterized, and their intensity increases with the number of self-assembled layers and redox charge. The characteristic infrared signatures are the 1040 cm-1 band assigned to the aromatic ligands in the osmium complex (î(Py)), PAH-Os, and the 1040 cm-1 (îs(SO3, and aromatic bipyridine and pyridine groups have been characterized, and their intensity increases with the number of self-assembled layers and redox charge. The characteristic infrared signatures are the 1040 cm-1 band assigned to the aromatic ligands in the osmium complex (î(Py)), PAH-Os, and the 1040 cm-1 (îs(SO3-1 band assigned to the aromatic ligands in the osmium complex (î(Py)), PAH-Os, and the 1040 cm-1 (îs(SO3î(Py)), PAH-Os, and the 1040 cm-1 (îs(SO3 -)) and 1213 cm-1 (îa(SO3)) and 1213 cm-1 (îa(SO3 -)) bands for SO3 groups in PVS. The îs(SO3)) bands for SO3 groups in PVS. The îs(SO3îs(SO3 -) vibrational mode of PVS senses the localNH3 + environment of the cationicPAH-Os resulting in a band shift of 22 cm-1 for the first polyallylamine layer. Subtractively normalized Fourier transform infrared spectroscopy during the oxidation of the Os centers in the (PAH-Os)n(PVS)m multilayer reveals that different vibrational modes of bipyridine ligands in the osmium redox center of PAH-Os and the sulfonate groups of PVS are affected by charge-ligand electrostatic interaction and dipole reorganization in the multilayers.) vibrational mode of PVS senses the localNH3 + environment of the cationicPAH-Os resulting in a band shift of 22 cm-1 for the first polyallylamine layer. Subtractively normalized Fourier transform infrared spectroscopy during the oxidation of the Os centers in the (PAH-Os)n(PVS)m multilayer reveals that different vibrational modes of bipyridine ligands in the osmium redox center of PAH-Os and the sulfonate groups of PVS are affected by charge-ligand electrostatic interaction and dipole reorganization in the multilayers.-1 for the first polyallylamine layer. Subtractively normalized Fourier transform infrared spectroscopy during the oxidation of the Os centers in the (PAH-Os)n(PVS)m multilayer reveals that different vibrational modes of bipyridine ligands in the osmium redox center of PAH-Os and the sulfonate groups of PVS are affected by charge-ligand electrostatic interaction and dipole reorganization in the multilayers.-Os)n(PVS)m multilayer reveals that different vibrational modes of bipyridine ligands in the osmium redox center of PAH-Os and the sulfonate groups of PVS are affected by charge-ligand electrostatic interaction and dipole reorganization in the multilayers.-Os and the sulfonate groups of PVS are affected by charge-ligand electrostatic interaction and dipole reorganization in the multilayers.-ligand electrostatic interaction and dipole reorganization in the multilayers.