Oxidation products of Nb{sub 4}W{sub 13}O{sub 47}: A transmission electron miscroscopy study

Journal Article · Fri Dec 01 04:00:00 EST 1995 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1006/jssc.1995.1408· OSTI ID:283007

Krumeich, F ^[1]; Gruehn, R ^[2]

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1. Universitat Bonn, Romerstrasse (Germany)
2. Universitat Gieben, Giessen (Germany)

Nb{sub 4}W{sub 13}O{sub 47}, a mixed valency oxide crystallizing in the structure of the 4:9 phase (4Nb{sub 2}O{sub 5}.9WO{sub 3}), was oxidized at various temperatures. The products have been characterized by high-resolution transmission electron microscopy. Oxidation products obtained at 600 and 1000{degrees}C exhibit the development of planar defects running along (110) of the TTB subcell. The defects built up by structural elements observed here for the first time: Two or more five-membered rings of octahedra are connected via two common octahedra. These arrays are combined with blocks of ReO{sub 3}-type structure and ordered along the defect planes. The oxidation at 1200{degrees}C leads to a separation into the 2:7 phase and WO{sub 3}.

• OSTI ID: 283007
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 2 Vol. 120; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
CRYSTAL DEFECTS
NIOBIUM OXIDES
OXIDATION
PHASE STUDIES
TRANSMISSION ELECTRON MICROSCOPY
TUNGSTEN OXIDES