Cascade catalysis of highly active bimetallic Au/Pd nanoclusters: structure-function relationship investigation using anomalous small-angle X-ray scattering and UV-Vis spectroscopy
Författare
Summary, in English
Recently, a so-called 'crown-jewel' concept of preparation of Au/Pd-based colloidal nanoclusters has been reported [Zhang, Watanabe, Okumura, Haruta & Toshima (2011). Nat. Mater. 11, 49-52]. Here, a different way of preparing highly active Au/Pd-based nanoclusters is presented. The origin of the increased activity of Au/Pd-based colloidal bimetallic nanoclusters was unclear up to now. However, it is, in general, accepted that in the nanometre range (1-100 nm) the cluster size, shape and composition affect the structural characteristics (e. g. lattice symmetry, unit cell), electronic properties (e. g. band gap) and chemical properties (e. g. catalytic activity) of a material. Hence, a detailed study of the relationship between the nanostructure of nanoclusters and their catalytic activity is presented here. The results indicate that a high surface-to-volume ratio of the nanoclusters combined with the presence of 'both' Au and Pd isolated regions at the surface are crucial to achieve a high catalytic activity. A detailed structure elucidation directly leads to a mechanistic proposal, which indeed explains the higher catalytic activity of Au/Pd-based catalysts compared with pure metallic Au or Pd. The mechanism is based on cascade catalysis induced by a single type of nanoparticle with an intermixed surface of Au and Pd.
Avdelning/ar
Publiceringsår
2013
Språk
Engelska
Sidor
1353-1360
Publikation/Tidskrift/Serie
Journal of Applied Crystallography
Volym
46
Dokumenttyp
Artikel i tidskrift
Förlag
International Union of Crystallography
Ämne
- Physical Sciences
- Natural Sciences
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1600-5767