Characterization and Reactivity of Mo₂C

Two types of Mo₂C have been investigated: polycrystalline β-Mo₂C and single crystal α-Mo₂C. The β-Mo₂C material was synthesized via a temperature-programmed method, and then characterized using x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), CO chemisorption, and N₂ physisorption. The catalytic activity of the β-Mo₂C was tested for cumene hydrogenation under high pressure conditions, and the effect of sulfur and oxygen poisons on cumene hydrogenation was also investigated. As a complement to the work done on polycrystalline β-Mo₂C, UHV studies of single crystal α-Mo₂C were undertaken to provide fundamental information about a well-characterized Mo₂C surface. The (0001) surface of α-Mo₂C was investigated using XPS and low energy electron diffraction (LEED). It was found that an ion-bombarded surface could be prepared as either Mo-terminated or C-terminated by choosing either low annealing temperatures (~1000 K) or high annealing temperatures (~1500 K), respectively. CO and O₂ adsorption was also studied on α-Mo₂C (0001) using thermal desorption spectroscopy (TDS), XPS, Auger electron spectroscopy (AES), and LEED. Finally, thiophene adsorption was investigated on α-Mo₂C (0001).

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Chemical Engineering

Department dc:contributor.department

Chemical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1998

Author dc:creator

• St. Clair, Todd P.

Chair dc:contributor.committeechair

• Cox, David F.

Committee members dc:contributor.committeemember

• Hochella, Michael F. Jr.
• Dillard, John G.
• Hanson, Brian E.
• Oyama, Shigeo Ted

• single crystal molybdenum carbide
• thiophene desulfurization

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-51898-10285

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/40502