Microwave assisted fluidized bed synthesis of catalytic nanolayers

The continuing focus of the research conducted under my part of the REU program has been the synthesis of catalytic nanolayers. These nanolayers have applications in low temperature fuel cells where they would convert carbon monoxide and water to carbon dioxide and hydrogen fuel through the water gas shift reaction. These catalytic nanolayers also have application in the hydrodenitrogenation and hydrodesulfurization of hydrocarbon fuels for cleaner burning.

The synthesis of the catalytic nanolayers as has been investigated under the REU program for the last three years has involved the combination of microwave heating to drive the nanolayer forming surface reactions and a fluidized bed to improve interaction between particles in the fluidized bed and the reactant gas. In particular, the latest REU research has used molybdenum particles fluidized in ethene gas as a means for synthesizing molybdenum carbide using techniques based on our prior work.

Prior work has successfully led to the formation of group VI transition metal nitrides such as chromium nitride and molybdenum nitride. Prior and current work is extending the experimental technique to the synthesis of group VI transition metal carbides since these have greater catalytic activity and improved stability compared to the nitrides. The extension of the work involves using an electronically controlled microwave oven that can deliver more power in short time periods. Further extension involves creating a fluidized bed that extends outside the heating chamber of the microwave oven so that flammable reactant gases such as ethylene can be used to synthesize carbides. Preliminary work this summer indicates that these changes may lead to the production of molybdenum carbide in the quantity necessary for sustained testing of catalytic activity. It is the research plan for this work to continue to use undergraduate researchers under the supervision of Prof. Brezinsky and his graduate and post-doctoral students to improve further the synthesis methodology and to investigate the catalytic activity of the various transition metal carbide nanolayers produced.

The involvement of undergraduates in this synthesis research program has been particularly fruitful. Not only have the undergraduates made scientific presentations both at the University and at national meetings but also have had the real life experience of working in a research laboratory. Since the students who have worked on the synthesis project have come from demonstrably underrepresented groups – Latinos and women, this real life research experience has served one of the primary goals of the REU program, the exposure of underrepresented group members to a research experience that may suggest to them the possibility of seeking a graduate education.