SUMMER RESEARCH TRAINING IN MEMBRANE SCIENCE AND TECHNOLOGY 2008 NSF REU SITE PROGRAM at the UNIVERSITY OF CINCINNATI
The Department of Chemical & Materials Engineering, College of Engineering is pleased to offer this research project as part of the 2008 summer NSF-REU Site Program administered by the Department of Pharmacology & Cell Biophysics.  Students interested in this project are urged to contact Professor Angelopoulos to discover more about the project, learn what your responsibilities will be during the ten-week research training program.
Project #:  08 - 001                    Faculty Supervisor/Mentor: Anastasios P. Angelopoulos, Ph.D., Assistant Professor, Department of Chemical and Materials Engineering, College of Engineering, University of Cincinnati Email: anastasios.angelopoulos@ uc.edu
Understanding Shear Thinning Behavior of Catalyst Inks Used in Fuel Cells
General background and significance of the project: Electrodes employed in proton exchange membrane (PEM) fuel cells are fabricated by applying colloidal catalyst inks (or pastes) onto perfluorosulfonate ionomer (PFSI) membranes. Constituent phases of the ink include PFSI, solvents (water and various alcohols), carbon supported catalyst, and other additives which assist in the coating process.  The ink is a complex fluid which undergoes substantial shear thinning during the mixing and coating processes.  The impact of such shear thinning on the distribution of the constituent phases, their interaction, and consequent fuel cell performance is uncertain.  One of the goals of Dr. Angelopoulos’ research group is to improve fundamental understanding in this area.  The specific REU project will help determine the impact of PFSI aggregate size distribution on the physical and electrochemical characteristics of the catalyst inks.
Brief description of proposed research and activities for the 10-week REU period: The REU student will characterize the aggregate size distribution of various PFSI dispersions as a function of solvent composition, equivalent weight, and concentration.  Characterization techniques employed include Dynamic Light Scattering (DLS), Cone and Plate Viscometry, and Field Emission Scanning Electron Microscopy (FESEM).  The REU student will use these three techniques provide complementary information concerning aggregate size.  In a separate project, carbon supported catalyst will be incorporated into the dispersions prepared by the student to produce catalyst inks.  The resultant shear thinning behavior, particle size distribution, and electrochemical activity of the inks will be assessed.  The most promising inks will then be used to produce membrane electrode assemblies (MEA’s) whose performance will be monitored under various operating conditions in industrial fuel cell stacks.
What the REU Student can gain from participating in this project: The REU student will be exposed to the most recent developments in PEM fuel cell materials.  The REU student will gain an appreciation of the highly multi-disciplinary nature of materials development today’s fuel cell industry, relying as it does on knowledge of surface chemistry, materials science, electrochemistry, chemical engineering, and systems and control engineering.  Finally, the REU student will gain experience communicating their findings in both written and oral formats to experts in the fuel cell industry.  Significant contributions made by the REU student will result in co-authorship on conference presentations and papers, and peer-reviewed articles arising from the research.