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Title: Charge transport properties in microcrystalline KDyFe(China){sub 6}

Abstract

Microcrystalline solid dysprosium(III) hexacyanoferrate(II) was synthesized by co-precipitation in aqueous solution. The resulting solid has been studied by Fourier transform infrared spectroscopy, X-ray analysis and solid state electrochemistry. The use of a cavity microelectrode was necessary to explore a wide range of time scale and minimize the (undesired) capacitive currents. Cyclic voltametric experiments were very helpful to understand the kinetic of charge transfer in such microstructure. A structure-properties relationship has been established from the crystallographic and the electrochemical properties. A square-scheme is presented to explain the unique electrochemical behavior of hexacyanoferrate containing dysprosium since this compound exhibits a second redox system. The solid presents an open channel-like morphology in which the motion of charged species occurs during the redox processes. Precisely, the electronic transfer is accompanied by a cation diffusion inside the microcrystalline structure. The size of these channels strongly suggests that the kinetic of charge transfer is limited by the cation transport into these structures. - Graphical abstract: Dy and Fe polyhedra packing in the cell of KDyFe(China){sub 6}.3.5H{sub 2}O shows occluded water molecules and potassium ions forming a pseudohexagonal 2D sub-lattice connected to each other by diffusion channels.

Authors:
 [1];  [2];  [1];  [1]
  1. Laboratoire de Physico-Chimie des Polymeres et des Interfaces (LPPI), Universite de Cergy-Pontoise, 5 Mail Gay-Lussac, Neuville-sur-Oise 95031, Cergy-Pontoise Cedex (France)
  2. Laboratoire de Physico-Chimie des Polymeres et des Interfaces (LPPI), Universite de Cergy-Pontoise, 5 Mail Gay-Lussac, Neuville-sur-Oise 95031, Cergy-Pontoise Cedex (France), E-mail: fabrice.goubard@u-cergy.fr
Publication Date:
OSTI Identifier:
21015708
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 2; Other Information: DOI: 10.1016/j.jssc.2006.12.004; PII: S0022-4596(06)00638-4; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; AQUEOUS SOLUTIONS; CHARGE TRANSPORT; COPRECIPITATION; CRYSTALLOGRAPHY; DYSPROSIUM COMPOUNDS; ELECTROCHEMISTRY; FERRATES; FOURIER TRANSFORM SPECTROMETERS; MICROSTRUCTURE; MORPHOLOGY; POTASSIUM COMPOUNDS; POTASSIUM IONS; REDOX PROCESS

Citation Formats

Aubert, P.H., Goubard, F., Chevrot, C., and Tabuteau, A. Charge transport properties in microcrystalline KDyFe(China){sub 6}. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2006.12.004.
Aubert, P.H., Goubard, F., Chevrot, C., & Tabuteau, A. Charge transport properties in microcrystalline KDyFe(China){sub 6}. United States. doi:10.1016/j.jssc.2006.12.004.
Aubert, P.H., Goubard, F., Chevrot, C., and Tabuteau, A. Thu . "Charge transport properties in microcrystalline KDyFe(China){sub 6}". United States. doi:10.1016/j.jssc.2006.12.004.
@article{osti_21015708,
title = {Charge transport properties in microcrystalline KDyFe(China){sub 6}},
author = {Aubert, P.H. and Goubard, F. and Chevrot, C. and Tabuteau, A.},
abstractNote = {Microcrystalline solid dysprosium(III) hexacyanoferrate(II) was synthesized by co-precipitation in aqueous solution. The resulting solid has been studied by Fourier transform infrared spectroscopy, X-ray analysis and solid state electrochemistry. The use of a cavity microelectrode was necessary to explore a wide range of time scale and minimize the (undesired) capacitive currents. Cyclic voltametric experiments were very helpful to understand the kinetic of charge transfer in such microstructure. A structure-properties relationship has been established from the crystallographic and the electrochemical properties. A square-scheme is presented to explain the unique electrochemical behavior of hexacyanoferrate containing dysprosium since this compound exhibits a second redox system. The solid presents an open channel-like morphology in which the motion of charged species occurs during the redox processes. Precisely, the electronic transfer is accompanied by a cation diffusion inside the microcrystalline structure. The size of these channels strongly suggests that the kinetic of charge transfer is limited by the cation transport into these structures. - Graphical abstract: Dy and Fe polyhedra packing in the cell of KDyFe(China){sub 6}.3.5H{sub 2}O shows occluded water molecules and potassium ions forming a pseudohexagonal 2D sub-lattice connected to each other by diffusion channels.},
doi = {10.1016/j.jssc.2006.12.004},
journal = {Journal of Solid State Chemistry},
number = 2,
volume = 180,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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