Interaction of oxygen with the (111) surface of NaAu2

SURFACE SCIENCE

卷:650

Article

Kwolek, Emma J.¹  Widmer, Roland²  Groning, Oliver²  Deniz, Okan²  Walen, Holly¹  Yuen, Chad D.^1,6  Huang, Wenyu¹  Schlagel, Deborah L.³  Wallingford, Mark³  Brundle, C. R.⁴  Thiel, Patricia A.^1,3,5 

[1] Iowa State Univ, Dept Chem, Ames, IA 50011 USA

[2] Swiss Fed Labs Mat Sci & Technol, EMPA, Nanotech Surfaces Lab, Ueberlandstr 129, CH-8600 Dubendorf, Switzerland

[3] Ames Lab, Ames, IA 50011 USA

[4] CR Brundle & Associates, 4215 Fairway Dr, Soquel, CA 95073 USA

[5] Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA

[6] Augustana Coll, Dept Chem & Biochem, Rock Isl, IL 61201 USA

关键词: XPS;    NaAu2;    Intermetallic;    Oxidation;   

DOI  :  10.1016/j.susc.2015.12.015

来源: Elsevier

【 摘 要 】

NaAu2, in powder form, is known to be an active catalyst for CO oxidation. The goal of the present study is to elucidate the interaction of one reactant, molecular oxygen, with a single-crystal surface of this material, NaAu2(111). Exposing the clean surface to gas-phase molecular oxygen produces three types of oxygen on the surface. One type is bound in spurious carbonate that forms during exposure. The second is adsorbed atomic oxygen that interacts both with Na and Au. The third type is atomic oxygen that interacts mainly or only with Na. We propose that the last species is an oxide of Na distributed throughout the surface and near-surface region. Its formation is accompanied by surface segregation of Na. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free