Hydrogen, Methanol, and Ethanol Catalytic Transformations on Transition Metals and Alloys

The combination of increasing energy world demand and the need to decrease our environmental footprint has emphasized the need for more efficient chemical processes. Catalysis has long been a way to improve process efficiency, by allowing processes to run using milder reaction conditions while obtaining higher selectivity and yields. Recently, surface science and computational techniques have been utilized to improve catalyst design. In particular, density function theory (DFT) calculations have been used to better understand catalytic reactions and suggest improvements. Together with sophisticated catalyst synthesis and characterization techniques, DFT calculations can aid in the following three key areas related to rational catalytic design: (1) finding trends in fundamental physical and chemical processes common to general catalytic reactions such as adsorption and diffusion; (2) modeling the potential energy surface of specific catalytic reactions and predicting the behavior of a given catalyst under realistic reaction conditions; and (3) suggesting novel catalyst formulations to provide for more economical and efficient catalysts.;In this dissertation, I provide examples of using DFT and complementary tools to accomplish all three of these aims. An in-depth look at hydrogen adsorption and diffusion on transition metals and alloy surfaces is included to enhance understanding of these phenomena, which are of interest both from a fundamental and applied standpoint. Models of methanol electroxidation and ethanol decomposition are proposed on the basis of DFT calculations to better understand the reaction pathways of each reaction and predict the behavior of relevant catalysts under realistic conditions. The findings of these models are compared to experimental work, such as the structure sensitivity of methanol electroxidation the activity of ethanol decomposition on real catalysts. Based on the above work, several novel catalyst formulations are identified with unique properties. Hydrogen adsorption on novel alloy surfaces is described, following which these alloy surfaces are synthesized and characterized. A new methanol electroxidation catalyst, Pt-Cu, is also proposed based on the DFT models. Characterization of the synthesized catalyst shows a synergistic effect between the two alloy components, as predicted by the model.