Application of high-resolution electron energy-loss spectroscopy to study the surface chemistry of metal oxides

High-resolution electron energy-loss spectroscopy (HREELS) has been used extensively during the past decade to probe the vibrational structure of adsorbed species on metal surfaces. Unfortunately, previous studies of adsorbates on metal oxides by HREELS have been limited due to the domination of the spectrum by losses due to the excitation of surface optical phonons and as well as charging of insulating oxides. In this work, a Fourier deconvolution method to remove combination modes from the energy loss spectrum and a charge stabilization technique to collect HREEL spectra from insulating oxides were further developed, which allowed HREELS to be applied to the study of the surface chemistry of metal oxides. The Fourier methods allowed losses associated with adsorbed surface species to be deconvoluted from the intense features due to the phonon modes of the oxides. The utility of these techniques was illustrated by examining the adsorption and reaction of carboxylates and hydrocarbons on ZnO, $\rm TiO\sb2,$ and MgO single crystal surfaces. In addition, HREELS was used to analyze the interactions between deposited Pt layers and the polar surfaces of ZnO. This work demonstrated the importance of local structure in determining the electronic interactions at metal/metal oxide interfaces. This thesis represents a significant advancement in the use of HREELS to study the reactivity of metal oxide surfaces