Pt Monolayer on Fe(001) Catalyst for O2 Reduction: A First Principles Study

• Escaño Mary Clare Sison

  Department of Precision Science & Technology and Applied Physics, Osaka University, Japan

• Kishi Tomoya

  Department of Precision Science & Technology and Applied Physics, Osaka University, Japan

• Kunikata Shinichi

  Department of Precision Science & Technology and Applied Physics, Osaka University, Japan

• Nakanishi Hiroshi

  Department of Precision Science & Technology and Applied Physics, Osaka University, Japan

• Kasai Hideaki

  Department of Precision Science & Technology and Applied Physics, Osaka University, Japan

Abstract

The results of spin-polarized density functional theory calculations for O₂ dissociative adsorption on Pt monolayer on Fe(001) (Pt_ML/Fe(001)) structure are presented and are compared with that of Pt(001). The potential energy curves for the reaction of Pt with O₂ as a function of O₂ center-of-mass distance from the platinum layer and O-O interatomic distance show that Pt_ML/Fe(001) produces a combination of lower activation barrier for O₂ dissociation and weaker O-atom binding which are both beneficial for a easier O₂ dissociation to produce adsorbed O and for subsequent reactions of O with other surface species for O₂ reduction process. Local density of states at Pt surface shows induced spin polarization on the Pt atomic layer characterized by d_zz peak at the Fermi level, in good agreement with experimental findings. Such effect increases unfilled d_zz orbital on Pt surface modifying Pt electronic surface structure towards a favorable O₂-Pt d interaction. Decrease in the magnetic moments of O and Pt atoms upon O adsorption indicates an antiparallel O unpaired electron spin alignment with Pt spin rendering consequent stabilization and a lowering of energy cost to O₂ activation. On the other hand, the weaker O binding reflects the stronger Pt-Fe interlayer bonding typical for such bimetallic systems. [DOI: 10.1380/ejssnt.2007.117]

Journal

• e-Journal of Surface Science and Nanotechnology

  e-Journal of Surface Science and Nanotechnology 5 117-121, 2007

  The Japan Society of Vacuum and Surface Science

Keywords

• Density functional calculations
• Catalysis
• Oxygen
• Metallic surfaces
• Iron
• Dissociation

Details

• CRID: 1390282680163026304
• NII Article ID: 130004439070
• DOI: 10.1380/ejssnt.2007.117
• ISSN: 13480391
• Web Site: http://www.jstage.jst.go.jp/article/ejssnt/5/0/5_0_117/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed