Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions

We describe electrochemical quartz crystal microbalance measurements on poly(o-toluidine) (PoT) films exposed to aqueous perchloric acid solutions (pH 0 to 2). Crystal impedance measurements show the films to behave rigidly. PoT redox switching occurs in two stages and is accompanied by nonmonotonic...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Ramirez, S., Hillman, A.R.
Formato:	JOUR
Materias:	Aromatic polymers Composition effects Conductive films Cyclic voltammetry Electric impedance measurement Electrolytes Inorganic acids Ion exchange Quartz applications Reaction kinetics Redox reactions Solvents Electrochemical quartz crystal microbalance Perchloric acid Polytoluidine Electrochemical electrodes
Acceso en línea:	http://hdl.handle.net/20.500.12110/paper_00134651_v145_n8_p2640_Ramirez
Aporte de:	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires

id	todo:paper_00134651_v145_n8_p2640_Ramirez
record_format	dspace
spelling	todo:paper_00134651_v145_n8_p2640_Ramirez2023-10-03T14:10:43Z Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions Ramirez, S. Hillman, A.R. Aromatic polymers Composition effects Conductive films Cyclic voltammetry Electric impedance measurement Electrolytes Inorganic acids Ion exchange Quartz applications Reaction kinetics Redox reactions Solvents Electrochemical quartz crystal microbalance Perchloric acid Polytoluidine Electrochemical electrodes We describe electrochemical quartz crystal microbalance measurements on poly(o-toluidine) (PoT) films exposed to aqueous perchloric acid solutions (pH 0 to 2). Crystal impedance measurements show the films to behave rigidly. PoT redox switching occurs in two stages and is accompanied by nonmonotonic mass changes that are the result of perchlorate counterion, proton co-ion, and solvent transfers. The extent and rate of each of these transfers are dependent upon electrolyte concentration, experimental time scale, and the switching potential, so that observations in a single electrolyte on a fixed time scale cannot be unambiguously interpreted. In the first and second oxidation stages, respectively, electroneutrality is satisfied predominantly by anion entry and proton exit. Throughout, there is solvent expulsion, to the extent of up to three water molecules per redox site converted. Transient experiments allow partial separation of the total mass change into individual species contributions. As the electrolyte concentration is decreased, there is progressive failure to establish first solvation, then co-ion transfer, then redox (electron/counterion transfer) equilibria. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00134651_v145_n8_p2640_Ramirez
institution	Universidad de Buenos Aires
institution_str	I-28
repository_str	R-134
collection	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic	Aromatic polymers Composition effects Conductive films Cyclic voltammetry Electric impedance measurement Electrolytes Inorganic acids Ion exchange Quartz applications Reaction kinetics Redox reactions Solvents Electrochemical quartz crystal microbalance Perchloric acid Polytoluidine Electrochemical electrodes
spellingShingle	Aromatic polymers Composition effects Conductive films Cyclic voltammetry Electric impedance measurement Electrolytes Inorganic acids Ion exchange Quartz applications Reaction kinetics Redox reactions Solvents Electrochemical quartz crystal microbalance Perchloric acid Polytoluidine Electrochemical electrodes Ramirez, S. Hillman, A.R. Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions
topic_facet	Aromatic polymers Composition effects Conductive films Cyclic voltammetry Electric impedance measurement Electrolytes Inorganic acids Ion exchange Quartz applications Reaction kinetics Redox reactions Solvents Electrochemical quartz crystal microbalance Perchloric acid Polytoluidine Electrochemical electrodes
description	We describe electrochemical quartz crystal microbalance measurements on poly(o-toluidine) (PoT) films exposed to aqueous perchloric acid solutions (pH 0 to 2). Crystal impedance measurements show the films to behave rigidly. PoT redox switching occurs in two stages and is accompanied by nonmonotonic mass changes that are the result of perchlorate counterion, proton co-ion, and solvent transfers. The extent and rate of each of these transfers are dependent upon electrolyte concentration, experimental time scale, and the switching potential, so that observations in a single electrolyte on a fixed time scale cannot be unambiguously interpreted. In the first and second oxidation stages, respectively, electroneutrality is satisfied predominantly by anion entry and proton exit. Throughout, there is solvent expulsion, to the extent of up to three water molecules per redox site converted. Transient experiments allow partial separation of the total mass change into individual species contributions. As the electrolyte concentration is decreased, there is progressive failure to establish first solvation, then co-ion transfer, then redox (electron/counterion transfer) equilibria.
format	JOUR
author	Ramirez, S. Hillman, A.R.
author_facet	Ramirez, S. Hillman, A.R.
author_sort	Ramirez, S.
title	Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions
title_short	Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions
title_full	Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions
title_fullStr	Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions
title_full_unstemmed	Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions
title_sort	electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions
url	http://hdl.handle.net/20.500.12110/paper_00134651_v145_n8_p2640_Ramirez
work_keys_str_mv	AT ramirezs electrochemicalquartzcrystalmicrobalancestudiesofpolyorthotoluidinefilmsexposedtoaqueousperchloricacidsolutions AT hillmanar electrochemicalquartzcrystalmicrobalancestudiesofpolyorthotoluidinefilmsexposedtoaqueousperchloricacidsolutions
_version_	1807315508591067136

Electrochemical quartz crystal microbalance studies of poly(ortho-toluidine) films exposed to aqueous perchloric acid solutions

Ejemplares similares