X-ray absorption spectroscopy aids improvement of fuel cell performance

Platinum is the most efficient electrocatalyst for accelerating chemical reactions in fuel cells for electric vehicles. However, the reactions that take place during the stop-and-go driving of an electric car cause the platinum to dissolve, which reduces its efficiency as a catalyst. Recently, a Brookhaven National Lab group led by Dr. R. Adzic found that adding gold clusters to the platinum electrocatalyst is effective in stabilizing and prolonging the life of the electrocatalyst. The group tested the performance under the oxidizing conditions of the O₂ reduction reaction and potential cycling between 0.6 and 1.1 V in over 30,000 cycles, and obtained successful results. X-ray absorption spectra measured at the Pt LIII edge clearly showed that the Au clusters contribute to protecting the platinum from being oxidized. The next step of the research is to duplicate the results in real fuel cells. For more information, see the paper, "Stabilization of Platinum Oxygen-Reduction Electrocatalysts Using Gold Clusters", J. Zhang et al., Science, 315, 220 (2007).