Compounds of molybdenum and tungsten with high specific surface area: carbides

Journal Article · Tue Oct 01 00:00:00 EDT 1985 · J. Solid State Chem.; (United States)

DOI:https://doi.org/10.1016/0022-4596(85)90302-0· OSTI ID:6086102

Volpe, L; Boudart, M

Temperature-programmed carburization of W/sub 2/N and Mo/sub 2/N powders in CH/sub 4/-H/sub 2/ mixtures up to 1150 and 970 K, respectively, leads to metastable face-centered cubic carbide phases. The reaction is topotactic in the sense that the face-centered cubic structure of the metal atoms remains unaltered, while the nitrogen and carbon atoms exchange their interstitial positions. Thus, the product retains the structure, crystallite size, and high specific surface area of its nitride parent, namely, 55 and 185 m/sup 2/g/sup -1/ for ..beta..-WC /SUB 1-x/ and ..cap alpha..-MoC /SUB 0.45/ , respectively.

• Research Organization: Department of Chemical Engineering, Stanford University, Stanford, CA
• OSTI ID: 6086102
• Journal Information: J. Solid State Chem.; (United States), Journal Name: J. Solid State Chem.; (United States) Vol. 59:3; ISSN JSSCB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
CARBIDES
CARBON COMPOUNDS
CARBURIZATION
CHEMICAL REACTION KINETICS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
CRYSTALLIZATION
CRYSTALS
CUBIC LATTICES
ENERGY LEVELS
EXCITED STATES
HARDENING
HIGH TEMPERATURE
ION EXCHANGE
KINETICS
METASTABLE STATES
MOLYBDENUM CARBIDES
MOLYBDENUM COMPOUNDS
MOLYBDENUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
PHASE STUDIES
PHASE TRANSFORMATIONS
PNICTIDES
REACTION KINETICS
REFRACTORY METAL COMPOUNDS
SURFACE HARDENING
SURFACE PROPERTIES
SURFACE TREATMENTS
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN CARBIDES
TUNGSTEN COMPOUNDS
TUNGSTEN NITRIDES
VERY HIGH TEMPERATURE