TransForum Vol. 7, No. 2

Catalyst Breakthrough Boosts Hydrogen Fuel Cells

Argonne researchers Nenad Markovic and Vojislav Stamenkovic with the new three-chamber ultra-high vacuum system used in their electrocatalysis work.

Our nation's dependence on foreign sources for transportation fuels threatens our economic and national security — but how do we overcome our dependence on petroleum products for transportation? A hydrogen economy based on fuel cells is one strategy. A key challenge in developing a hydrogen economy is reducing the amount of expensive platinum catalyst needed to operate fuel cells efficiently.

To overcome that challenge, Argonne researchers have discovered new information about the behavior of nano-engineered platinum surfaces that may bring polymer electrolyte membrane fuel cells for hydrogen-powered vehicles another step closer to full development.

Argonne researchers Nenad Markovic and Vojislav Stamenkovic — in collaboration with colleagues Philip Ross and Bongjin Mun at Lawrence Berkeley National Laboratory, Christopher Lucas from the University of Liverpool, and Guofeng Wang from the University of South Carolina — have recently discovered that a nanosegregated platinum-nickel alloy surface has unique catalytic properties. Their discovery opens up important new directions for the development of active and stable practical cathode catalysts in fuel cells. The findings were published in the January 2007 issue of the journal Science.

According to Stamenkovic, "This discovery sets a new bar for catalytic activity in fuel cells and makes it feasible to meet U.S. Department of Energy (DOE) targets for platinum-specific power densities without a loss in cell voltage. We have identified a cathode surface that is capable of achieving and even exceeding the target for catalytic activity, with improved stability for the cathodic reaction in fuel cells."

Stamenkovic further explained, "Although the platinum-nickel alloy itself is well-known, we were able to control and tune key parameters, which enabled us to make this discovery. Our study demonstrates the potential of new analytical tools for characterizing nanoscale surfaces in order to fine tune their properties in a desired direction."

George Crabtree, director of Argonne's Materials Science Division, emphasized the path-breaking importance of the research: "It is not only world-class basic science, it is a major advance for energy research."

The research was funded by DOE's Office of Basic Energy Sciences, Office of Energy Efficiency and Renewable Energy-Hydrogen, Fuels Cells & Infrastructure Technology Program, and by General Motors.

August 27, 2007