Date of Award

12-2011

Degree Type

Dissertation

Degree Name

Doctor of Philosophy

Major

Chemistry

Major Professor

John Z. Larese

Committee Members

T. Ffrancon Williams, Michael J. Sepaniak, Jaime A. Fernandez-Baca

Abstract

Catalytically relevant metal clusters were deposited on metal oxide supports. Palladium and gold were deposited on mixed morphology ZnO, and palladium was deposited on MgO(100). The materials were characterized with electron microscopy, photoluminescent spectroscopy, and X-ray photoelectron spectroscopy. The behavior of hydrogen on these materials, as well as bare ZnO, was studied using volumetric isotherms. The isotherms were used to determine the monolayer gas coverage, surface

area, and heats of adsorption of hydrogen on these materials over the temperature range of approximately 8-13 K. At the temperatures and pressures studied, hydrogen physically adsorbed onto the materials. Additional investigations with inelastic neutron scattering were conducted on palladium decorated ZnO and bare ZnO. These revealed that hydrogen molecules on bare ZnO act as three dimensional free rotors, but hydrogen on palladium decorated ZnO acts as a two-dimensional planar molecule and undergoes a 6.2% bond length extension.

Files over 3MB may be slow to open. For best results, right-click and select "save as..."

Share

COinS