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Title: A new molecular precursor route for the synthesis of Bi-Y, Y-Nb and Bi-doped Y-Nb oxides at moderate temperatures

Abstract

Yttrium-based multimetallic oxides containing bismuth and/or niobium were prepared by a method starting from pre-isolated stable water-soluble precursors which are complexes with the ethylenediaminetetraacetate ligand (edta). The cubic Bi{sub 1-} {sub x} Y {sub x} O{sub 1.5} (x=0.22, 0.25 and 0.3) and Y{sub 3}NbO{sub 7} oxides were obtained in a pure form in a range of moderate temperatures (600-650 deg. C). This preparation method also allowed to stabilize at room temperature, without quenching, the tetragonal YNbO{sub 4} oxide in a distorted form (T'-phase) by calcining the precursor at 800 deg. C. When heated up to 1000 deg. C, this metastable T'-phase transforms into the metastable 'high-temperature' T oxide, which converts on cooling down to room temperature into the thermodynamically stable monoclinic M oxide. Doping the YNbO{sub 4} oxide with Bi{sup 3+} cations (0.5% and 1% Bi with respect to total Bi+Y amount) led at 800 deg. C to a mixture of the T'-phase and the thermodynamically stable monoclinic one. At 900 deg. C, the almost pure monoclinic structure was obtained. - Graphical abstract: Bi-Y, Nb-Y and Bi-doped Nb-Y oxides were prepared by a molecular precursors method from pre-isolated water-soluble edta-based complexes. The cubic Bi{sub 1-} {sub x} Y {sub x}more » O{sub 1.5} and Y{sub 3}NbO{sub 7} oxides were obtained in a pure form at the moderate temperature of 650 deg. C. A distorted tetragonal YNbO{sub 4} phase was also stabilized at room temperature by calcining the precursor at 800 deg. C, and the pure corresponding monoclinic oxide has been obtained near 1100 deg. C.« less

Authors:
 [1];  [1];  [2]
  1. Unite de Chimie des Materiaux Inorganiques et Organiques, Universite Catholique de Louvain, Place Louis Pasteur 1, B-1348 Louvain-la-Neuve (Belgium)
  2. Unite de Chimie des Materiaux Inorganiques et Organiques, Universite Catholique de Louvain, Place Louis Pasteur 1, B-1348 Louvain-la-Neuve (Belgium), E-mail: devillers@chim.ucl.ac.be
Publication Date:
OSTI Identifier:
21015757
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2007.01.027; PII: S0022-4596(07)00060-6; Copyright (c) 2007 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; BISMUTH IONS; BISMUTH OXIDES; CUBIC LATTICES; DOPED MATERIALS; EDTA; LIGANDS; MONOCLINIC LATTICES; NIOBIUM OXIDES; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TEMPERATURE RANGE 1000-4000 K; YTTRIUM OXIDES

Citation Formats

Bayot, D.A., Dupont, A.M., and Devillers, Michel M.. A new molecular precursor route for the synthesis of Bi-Y, Y-Nb and Bi-doped Y-Nb oxides at moderate temperatures. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2007.01.027.
Bayot, D.A., Dupont, A.M., & Devillers, Michel M.. A new molecular precursor route for the synthesis of Bi-Y, Y-Nb and Bi-doped Y-Nb oxides at moderate temperatures. United States. doi:10.1016/j.jssc.2007.01.027.
Bayot, D.A., Dupont, A.M., and Devillers, Michel M.. Thu . "A new molecular precursor route for the synthesis of Bi-Y, Y-Nb and Bi-doped Y-Nb oxides at moderate temperatures". United States. doi:10.1016/j.jssc.2007.01.027.
@article{osti_21015757,
title = {A new molecular precursor route for the synthesis of Bi-Y, Y-Nb and Bi-doped Y-Nb oxides at moderate temperatures},
author = {Bayot, D.A. and Dupont, A.M. and Devillers, Michel M.},
abstractNote = {Yttrium-based multimetallic oxides containing bismuth and/or niobium were prepared by a method starting from pre-isolated stable water-soluble precursors which are complexes with the ethylenediaminetetraacetate ligand (edta). The cubic Bi{sub 1-} {sub x} Y {sub x} O{sub 1.5} (x=0.22, 0.25 and 0.3) and Y{sub 3}NbO{sub 7} oxides were obtained in a pure form in a range of moderate temperatures (600-650 deg. C). This preparation method also allowed to stabilize at room temperature, without quenching, the tetragonal YNbO{sub 4} oxide in a distorted form (T'-phase) by calcining the precursor at 800 deg. C. When heated up to 1000 deg. C, this metastable T'-phase transforms into the metastable 'high-temperature' T oxide, which converts on cooling down to room temperature into the thermodynamically stable monoclinic M oxide. Doping the YNbO{sub 4} oxide with Bi{sup 3+} cations (0.5% and 1% Bi with respect to total Bi+Y amount) led at 800 deg. C to a mixture of the T'-phase and the thermodynamically stable monoclinic one. At 900 deg. C, the almost pure monoclinic structure was obtained. - Graphical abstract: Bi-Y, Nb-Y and Bi-doped Nb-Y oxides were prepared by a molecular precursors method from pre-isolated water-soluble edta-based complexes. The cubic Bi{sub 1-} {sub x} Y {sub x} O{sub 1.5} and Y{sub 3}NbO{sub 7} oxides were obtained in a pure form at the moderate temperature of 650 deg. C. A distorted tetragonal YNbO{sub 4} phase was also stabilized at room temperature by calcining the precursor at 800 deg. C, and the pure corresponding monoclinic oxide has been obtained near 1100 deg. C.},
doi = {10.1016/j.jssc.2007.01.027},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 180,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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