The bonding between an organometallic species and an oxide or nitride supporting substrate is important to the chemistry of supported catalysts, electronic device processing, and adhesion and lubrication phenomena. This bonding may be investigated with the aid of ultraviolet photoelectron spectroscopy (UPS) and X-ray photoelectron spectroscopy (XPS). When combined with other surface probes such as thermal desorption spectroscopy (TDS), AES, LEED, and vibrational spectroscopic characterization by high resolution electron energy loss spectroscopy (HREELS) or reflection-absorption infrared spectroscopy (RAIRS), a relatively complete picture of the surface properties of the adsorbed species becomes available. We are exploring, in collaboration with Professor Jeffrey Schwartz, the interaction of a number of transition metal and phosphonate complexes with well characterized oxide surfaces. In this work electron spectroscopic measurements are correlated with the chemical behavior of the supported complex, as studied by conventional heterogeneous catalysis methods and mass sensitive kinetic methods. This approach is also extended to the study of important oxide and nitride bound metallic layers, which are of interest in electronic materials chemistry, in bio-compatible materials chemistry, and in adhesion and corrosion inhibition applications. See, for example,

There are two main methods to inhibit corrosion of structural metals; one focuses on the design of corrosion resistant alloys, while the other involves protecting the surface with corrosion inhibitors.

Many industrial processes involve high-temperature corrosive conditions and require alloys capable of regenerative oxide layer growth to avoid structural failure. The growth of these protective oxide layers is studied with SEM (secondary electron microscopy), EDX (energy dispersive x-ray spectroscopy), and XPS (x-ray photoelectron spectroscopy). With these techniques, the different types of oxides can be distinguished and their kinetics better understood. The goal of this project is to understand in detail the capabilities of different alloys to grow compact, continuous and adherent oxide layers in situ.

Corrosion resistant alloys are not cost effective on the large scale needed for oil and gas wells and refinery applications. For these applications, a more cost effective and commonly used alternative is the injection of corrosion inhibitors into the well. These inhibitors protect the metal by physically blocking the surface corrosion sites. We analyze the interaction between the surface and inhibitor in order to determine the mechanism of corrosion inhibition. Current studies focus specifically on small molecules, mainly organic heterocycles, as corrosion inhibitors using EIS (electrochemical impedance spectroscopy) and XPS (x-ray photoelectron spectroscopy) to assess their effectiveness. ,

The collision of a gas molecule with a surface, followed by trapping of the molecule on the surface, must precede any surface reactions which might take place. Some knowledge of this fundamental process, along with the accompanying energy transfer to the surface, is essential to a complete understanding of heterogeneous reaction dynamics.The mechanism by which highly effiecient catalysts achieve their activity is of special interest in the energy sector, where novel catalysts could pave the way for practical fuel cells and other breakthrough technologies. We have investigated the detailed dynamics of a very important prototype surface reaction, the catalytic oxidation of CO on platinum. Our diode laser absorption spectrometer provides much better resolution and is sensitive to the possible production of cold CO₂ in the oxidation reaction. We have used this method to map out the detailed ro-vibrational populations of the product CO₂ and changes in these populations with changing surface reaction conditions. These studies have been extended to the reaction of CO with NO and methanol with O₂. Currently, we are extending the studies to investigate the catalytic oxidation of CO occuring on Pt nanoparticles deposited on bundles of carbon nanotubes. Ab-initio quantum calculations are used to map the electronic structure of the Pt/SWNT system. See, for example,