CO oxidation over AuPd(100) from ultrahigh vacuum to near-atmospheric pressures: the critical role of contiguous Pd atoms

Feng Gao; Yilin Wang; D Wayne Goodman

doi:10.1021/ja9008437

CO oxidation over AuPd(100) from ultrahigh vacuum to near-atmospheric pressures: the critical role of contiguous Pd atoms

J Am Chem Soc. 2009 Apr 29;131(16):5734-5. doi: 10.1021/ja9008437.

Authors

Feng Gao¹, Yilin Wang, D Wayne Goodman

Affiliation

¹ Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.

PMID: 19382813
DOI: 10.1021/ja9008437

Abstract

It is demonstrated that gas-phase CO pressure higher than approximately 0.1 Torr is required to segregate a sufficient amount of Pd to the surface of a well-annealed AuPd(100) sample to form contiguous Pd sites. These contiguous sites are critical in dissociating O(2) for low-temperature CO oxidation, where CO chemisorbed on Au sites clearly participates in the reaction at temperatures below approximately 400 K. Measured reaction kinetics demonstrates that the higher reaction rate is achieved on a surface with higher coverages of contiguous Pd sites.