Surface characterization and electrocatalytic activity of ordered intermetallic PtBi(001) surfaces by ultrahigh vacuum-electrochemistry (UHV-EC)

I&EC 149

Jean Sanabria-Chinchilla, js589@cornell.edu1, Hiedki Abe, ABE.Hideki@nims.go.jp2, F. J. DiSalvo, fjd3@cornell.edu1, and Hector D. Abruņa, hda1@cornell.edu1. (1) Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, (2) NIMS, Ibaraki, Japan
Surface characterization of an ordered intermetallic PtBi(001) single crystal have been performed by a combination of surface-sensitive electron spectroscopic techniques under ultra-high vacuum conditions and conventional electrochemistry. The clean surface was characterized by a chemical composition of 54 % Pt and 46 % Bi (Auger analysis). LEED patterns indicated that the surface was smooth and well-ordered with a hexagonal array of atoms. The electrochemical studies indicated that the electrode surface is Pt-terminated with a behavior similar to that of a pure Pt electrode. The intermetallic phase was more prone to chemisorption by oxygenated species over the studied potential window. The nature of this species was potential dependent. The crystal exhibited enhanced electrocatalytic activity for the oxidation of small organic molecules such as formic acid. A competition between the oxidation of the organics and surface oxide formation was observed. The presence of fuel retarded the electrochemically-induced changes on the electrode surface.
 

Nanotechnology and the Environment: Emphasis on Green Nanotechnology
8:30 AM-12:30 PM, Thursday, April 10, 2008 Morial Convention Center -- Rm. 231, Oral

Division of Industrial & Engineering Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008