COLL 31 |
| Since Haruta reported that Au nanoparticles are surprisingly active if prepared and deposited on suitable carriers [1], the activity of Au has become widely recognized for various reactions [2]. Catalytic properties of Au depend on the size and shape of Au particles [3], but also on the nature of the support or additives and their interaction with Au [4, 5]. Highly active Au/Al2O3 catalysts were prepared and tested in various reactions. Additives such as alkali (earth) metal oxides significantly influence the stability of Au nanoparticles against sintering (structural promoters). Additives such as ceria act as both structural and chemical promoters. However, the interaction between Au and additives is not fully understood. LEIS was used as a versatile technique to study the composition/structure of the multicomponent catalysts on the surface. For this purpose two representative systems were selected: Au/BaO/CeOx/Al2O3 and Au/Li2O/CeOx/Al2O3. The results are discussed in connection with the catalytic activity measurements. [1] M. Haruta, T. Kobayashi, N. Yamada, Chem. Lett. 2 (1987) 405. [2] A. C. Gluhoi, M. A. P. Dekkers, B. E. Nieuwenhuys, J. Catal. 219 (2003) 197. [3] A. Wolf, F. Schuth, Appl. Catal. A 226 (2002) 1. [4] A. C. Gluhoi, S. D. Lin, B. E. Nieuwenhuys, Catal. Today 90 (2004) 175. [5] A. C. Gluhoi, N. Bogdanchikova, B. E. Nieuwenhuys, J. Catal. 229 (2005) 154. |
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Correlation of Single Crystal Studies Using Surface Science Techniques to Industrial Catalysts
8:30 AM-11:30 AM, Sunday, 10 September 2006 Sir Francis Drake -- Tudor Room, Oral
Division of Colloid & Surface Chemistry |