The strong reactions of Lewis-base noble-metals with vanadium and other acidic transition metals

Thesis/Dissertation · Wed May 01 00:00:00 EDT 1991

DOI:https://doi.org/10.2172/10190695· OSTI ID:10190695

Ebbinghaus, Bartley B. ^[1]

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1. Univ. of California, Berkeley, CA (United States)

The noble metals often thought of as unreactive solids,react strongly with nearly 40% of the elements in the periodictable: group IIIB-VB transition metals, lanthanides, theactinides, and group IIIA-IVA non-transition metals. These strong reactions arise from increased bonding/electron transfer fromnonbonding electrons d electron pairs on the noble metal tovacant orbitals on V, etc. This effect is a generalized Lewis acid-base interaction. The partial Gibbs energy of V in the noblemetals has been measured as a function of concentration at a temperature near 1000C. Thermodynamics of the intermetallics are determined by ternary oxide equilibria, ternary carbide equilibria, and the high-temperature galvanic cell technique. These experimental methods use equilibrated solid composite mixtures in which grains of V oxides or of V carbides are interspersed with grains of V-NM(noble-metal) alloys. In equilibrium the activity of V in the oxide or the carbide equals the activity in the alloy. Consequently, the thermodynamics available in the literature for the V oxides and V carbides are reviewed. Test runs on the galvanic cell were attempted. The V oxide electrode reacts with CaF₂, ThO₂, YDT(0.85ThO₂-0.15YO_1.5), and LDT(0.85ThO₂- 0.15LaO_1.5) to interfere with the measured data observed toward the beginning of a galvanic cell experiment are the most accurate. The interaction of vanadium at infinite dilution in the noble-metals was determined.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 10190695
• Report Number(s): LBL-32737; ON: DE93002552
• Resource Relation: Other Information: TH: Thesis (Ph.D.); PBD: May 1991
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
PLATINUM METALS
CHEMICAL REACTIONS
TRANSITION ELEMENTS
PLATINUM METAL ALLOYS
INTERMETALLIC COMPOUNDS
TRANSITION ELEMENT ALLOYS
VANADIUM
VANADIUM ALLOYS
LEWIS BASES
LEWIS ACIDS
ELECTRON TRANSFER
PHASE DIAGRAMS
400201
360102
400400
CHEMICAL AND PHYSICOCHEMICAL PROPERTIES
STRUCTURE AND PHASE STUDIES
ELECTROCHEMISTRY