Seminars

DEPARTMENT OF CHEMISTRY, SEOUL NATIONAL UNIVERSITY.

Oxygen Reduction for Fuel Cells: Mechanistic Studies and the Design of New Catalysts

March 2, 2009l Hit 275
Date : March 5, 2009 17:00 ~
Speaker : Prof. Andrew A. Gewirth (University of Illinois, Department of Chemistry)
Location : Mogam Hall, Bldg 500

Date: 2009. 3. 5, 5:00 PM Place: Mogam Hall, Bldg 500 - Abstract - In this talk, we discuss aspects of our work related to the structure and reactivity of electrode surfaces. We report on our efforts directed at establishing the mechanism of oxygen and peroxide reduction on bare Pt and Cu, and on Au surfaces modified with order metal monolayers. By using a combination of spectroscopic, imaging, and x-ray scattering techniques combined with detailed calculations, we have shown that a crucial step involves the spontaneous clevage of the O-O bond to form a mixed metal-hydroxide complex. This hydroxide complex is reduced during the electron transfer event, leading to the product water. We also report on our extension of this activity toward the process of nitrate reduction. The understanding derived from the mechanistic work provides directions for synthesis of advanced catalysts for oxygen reduction. In particular, we have synthesized a series of bio-insipired metal coordination polymers exhibiting oxygen reduction activity.