Thumbnail
Access Restriction
Open

Author Krumeich, F. ♦ Gruehn, R.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword MATERIALS SCIENCE ♦ CHEMISTRY ♦ NIOBIUM OXIDES ♦ OXIDATION ♦ PHASE STUDIES ♦ TUNGSTEN OXIDES ♦ TRANSMISSION ELECTRON MICROSCOPY ♦ CRYSTAL DEFECTS
Abstract 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}.
ISSN 00224596
Educational Use Research
Learning Resource Type Article
Publisher Date 1995-12-01
Publisher Place United States
Journal Journal of Solid State Chemistry
Volume Number 120
Issue Number 2


Open content in new tab

   Open content in new tab