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

Journal Article · Thu Mar 15 04:00:00 EDT 2007 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2007.01.027· OSTI ID:21015757

Bayot, D A ^[1]; Dupont, A M ^[1]

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1. Unite de Chimie des Materiaux Inorganiques et Organiques, Universite Catholique de Louvain, Place Louis Pasteur 1, B-1348 Louvain-la-Neuve (Belgium)

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.

• OSTI ID: 21015757
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 3 Vol. 180; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

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