Chinese Journal of Catalysis ›› 2016, Vol. 37 ›› Issue (10): 1656-1661.DOI: 10.1016/S1872-2067(16)62501-9

• Communications • Previous Articles     Next Articles

Halogen adsorbates on polymer-stabilized gold clusters: Mass spectrometric detection and effects on catalysis

Ryo Ishidaa, Setsuka Ariia, Wataru Kurashigeb, Seiji Yamazoea,c, Kiichirou Koyasua,c, Yuichi Negishib, Tatsuya Tsukudaa,c   

  1. a Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyoku, Tokyo 113-0033, Japan;
    b Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan;
    c Elements Strategy Initiative for Catalysts and Batteries(ESICB), Kyoto University, Katsura, Kyoto 615-8520, Japan
  • Received:2016-05-06 Revised:2016-06-15 Online:2016-10-21 Published:2016-10-22
  • Contact: Tatsuya Tsukuda
  • Supported by:

    This work was supported by the Elements Strategy Initiative for Catalysts and Batteries (ESICB) and a Grant-in-Aid for Scientific Research (26248003, 15H01042) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan.

Abstract:

The mass spectrometry of gold clusters stabilized by poly(N-vinyl-2-pyrrolidone) (Au:PVP) revealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Changes in the amount of Cl adsorbates on the Au clusters did not affect the catalytic properties for the aerobic oxidation of benzyl alcohol, suggesting that the Cl atoms were only weakly bound to the Au clusters. In contrast, the replacement of Cl with Br on the Au34 and Au43 clusters significantly suppressed activity, without any influence on the electronic structure. This result indicated that the Br atoms were strongly bound to the Au clusters and sterically blocked their active sites. The substantial reduction of the catalytic activity by the Br adsorbates suggested that the Au34 and Au43 clusters made a major contribution to the catalytic activity of the Au:PVP.

Key words: Gold cluster, Poly(N-vinyl-2-pyrrolidone), Halogen adsorbates, Aerobic alcohol oxidation, Mass spectrometry