J. Phys. IV France 7 (1997) C2-953-C2-954
Pt LIII-Edge EXAFS Studies on Pt-Cu-Fe Alloy Electrocatalysts Supported on CarbonD.-K. Kim1, J.-H. Choy2, K.-S. Han3, S.-J. Hwang2, W. Roh2 and H. Kim2
1 Department of Chemistry, Kyungpook National University, Taegu 702-701, Korea
2 Department of Chemistry, Center for Molecular Catalysis, Seoul National University, Seoul 151-742 Korea
3 Inorganic Chemistry Division, National Institute of Technology and Quality, Kyunggi-do 427-010, Korea
Carbon supported Pt-Cu-Fe alloys with compositions of Pt:Cu:Fe=6:l:l and 2:l:l have been prepared. Both catalysts exhibit higher specific activities for oxygen reduction than Pt alone. In order to reveal the local structure around Pt, we have performed X-ray absorption experiment at the Pt LIII-edge. The local structure around Pt has been analyzed by fitting the first shell including the Pt-Pt, Pt-Cu, and Pt-Fe contributions to EXAFS spectra. The fitted C.N. for both alloys are similar to that for bulk Pt, indicating that the particle size is not small. The Pt-Pt distances for both alloys are found to be slightly shorter than that of bulk Pt, and the Pt-Cu and Pt-Fe distances decrease as the amounts of Cu and Fe increase. It is therefore concluded that the catalytic activity is strongly influenced by the bonding character.
© EDP Sciences 1997