Neil Schweitzer

Ph.D. Candidate
B.S.: Chemical Engineering 2004, University of Toledo

nschweit@umich.edu

Molybdenum carbide (Mo₂C) has been shown to be a highly active catalyst for several reactions, even rivaling the activity of precious metal catalysts such as platinum. Recently, a technique has been developed in which metal catalysts are loaded onto high surface area Mo₂C supports. The resulting catalysts have been shown to exhibit very high activity when compared to the activity of the support and the metal alone, displaying a synergistic effect between the two.

The source of this effect is thought to occur due to chemical means, but the possibility exists that the effect arises from physical differences between the catalysts, i.e. particle size and dispersion of the loaded metal. Attempts to measure these properties in the past have been unsuccessful.

The purpose of this project is to develop a fundamental understanding of the use of carbide materials as metal catalyst supports. This will be accomplished by studying the two major areas of interest mentioned above: physical effects and chemical effects. In this study, a new method for the quantification of the physical properties of the carbide support is presented along with preliminary experiments in which to study its veracity. This method can then be used to study the sintering characteristics of the catalyst, which in turn will be compared with that of the traditional (SiO₂, Al₂O₃) and nontraditional oxide supports (MoO₃).

Once the role of the physical characteristics of the catalyst to its overall activity has been determined, any chemical or electronic synergy can then be studied. This information will help contribute to the overall goal of this project: to develop predictive trends concerning the use of transition metal carbide supported metal catalysts for a wide range of chemical reactions.

This study will encompass traditional experimental techniques (chemisorption techniques, temperature programmed reduction, x-ray diffraction), ultra-high vacuum surface science techniques (x-ray photoelectron spectroscopy, scanning tunneling microscopy), and theoretical calculations (density functional theory) among other tools.