Theoretical Investigation on the Au-Anchor Site in Phosphate-Doped Au/Al₂O₃Catalysts

• Tada Kohei

  Department of Chemistry, Graduate School of Science, Osaka University

• Koga Hiroaki

  Element Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University

• Sakata Kohei

  Department of Chemistry, Graduate School of Science, Osaka University

• Oguni Atsushi

  Department of Chemistry, Graduate School of Science, Osaka University

• Saito Toru

  Department of Chemistry, Graduate School of Science, Osaka University

• Kawakami Takashi

  Department of Chemistry, Graduate School of Science, Osaka University

• Yamanaka Shusuke

  Department of Chemistry, Graduate School of Science, Osaka University

• Okumura Mitsutaka

  Department of Chemistry, Graduate School of Science, Osaka University Element Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University

Abstract

In order to clarify the Au-anchor site in phosphate-doped Al₂O₃ and investigate the mechanism of Au-stabilization by phosphate, density functional theory (DFT) calculations were carried out. We calculated Au atom adsorption onto three model surfaces, such as sAl₂O₃ (a stoichiometric Al₂O₃ surface), fPO–Al₂O₃ (an Al₂O₃ surface fully covered by phosphate), and pPO–Al₂O₃ (an Al₂O₃ surface partially covered by phosphate). The calculated results showed that the order of stability for Au atom adsorption onto these three model surfaces is Au/fPO-Al₂O₃ > Au/pPO-Al₂O₃ > Au/sAl₂O₃. When Au atom adsorbs to a phosphate-phosphate bridge site of fPO-Al₂O₃ surface, the stabilization of Au adsorption onto the surface is especially large (the adsorption energy of Au is −3.16 eV). This high stability of Au at the phosphate-phosphate bridge site is due to negative charge transfer from Au to Al₂O₃ surface, which makes Au–O bond more stable. Hence, we have concluded that “phosphate-phosphate bridge sites” anchor Au. [DOI: 10.1380/ejssnt.2015.380]

Journal

• e-Journal of Surface Science and Nanotechnology

  e-Journal of Surface Science and Nanotechnology 13 (0), 380-384, 2015

  The Japan Society of Vacuum and Surface Science

Keywords

• Density functional calculations
• Atom-solid interaction
• Catalysis
• Gold
• Aluminum oxide
• Phosphate
• Anchor site

Details

• CRID: 1390001205187232256
• NII Article ID: 130005089395
• DOI: 10.1380/ejssnt.2015.380
• ISSN: 13480391
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed