Return to search

Halocarbon Reactions on the Chromium (III) Oxide (101̲2) Surface

A nearly stoichiometric, (1×1) Cr₂O₃ (101̲2) surface was prepared from a single crystal of α-Cr₂O₃. The five-coordinate cations exposed at the stoichiometric surface dissociatively adsorb molecular oxygen to form a (1×1), terminating chromyl (Cr=O) layer that is stable to >1100 K. TDS and AES were used to investigate the reactivity of the halo-alkanes CFCl₂CH₂Cl, CF₂ClCH₂Cl, CF₃CH₂Cl, and CF₂CH₂F, in addition to the halo-alkenes CFCl=CH₂ and CF₂=CH₂. The halo-alkanes CFCl₂CH₂Cl, CF₂ClCH₂Cl, and CF₃CH₂Cl undergo 1,2-dihalo elimination similar to the Zn-catalyzed dehalogenation of vicinal dihalides to form alkenes. Some acetylene is also formed. The halo-alkenes CFCl=CH₂ and CF₂=CH₂ decompose to yield acetylene. Halogen removed from the molecules remains bound to the surface following TDS experiments and eventually terminates the surface chemistry due to site blocking of the cations. Reactivity is directly related to the chlorine content of the molecules investigated. Only CFCl₂CH₂Cl was reactive on a chromyl-terminated surface. / Ph. D.

Identiferoai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/39182
Date31 August 1999
CreatorsYork, Steven C.
ContributorsChemical Engineering, Cox, David F., Hanson, Brian E., Dillard, John G., Marand, Eva, Oyama, Shigeo Ted
PublisherVirginia Tech
Source SetsVirginia Tech Theses and Dissertation
Detected LanguageEnglish
TypeDissertation
Formatapplication/pdf
RightsIn Copyright, http://rightsstatements.org/vocab/InC/1.0/
RelationSCYdissertation-modified.pdf

Page generated in 0.0022 seconds