Article

A General Synthetic Strategy for Oxide-Supported Metal Nanoparticle Catalysts

Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society (Impact Factor: 12.11). 12/2006; 128(44):14278-80. DOI: 10.1021/ja0659929
Source: PubMed

ABSTRACT

Despite recent exciting progress in catalysis by supported gold nanoparticles, there remains the formidable challenge of preparing supported gold catalysts that collectively incorporate precise control over factors such as size and size-distribution of the gold nanoparticles, homogeneous dispersion of the particles on the support, and the ability to utilize a wide range of supports that profoundly affect catalytic performance. Here, we describe a synthetic methodology that achieves these goals. In this strategy, weak interface interactions evenly deposit presynthesized organic-capped metal nanoparticles on oxide supports. The homogeneous dispersion of nanoparticles on oxides is then locked in place, without aggregation, through careful calcination. The approach takes advantage of recent advances in the synthesis of metal and oxide nanomaterials and helps to bring together these two classes of materials for catalysis applications. An important feature is that the strategy allows metal nanoparticles to be well dispersed on a variety of oxides with few restrictions on their physical and chemical properties. Following this synthetic procedure, we have successfully developed efficient gold catalysts for green chemistry processes, such as the production of ethyl acetate from the selective oxidation of ethanol by oxygen at 100 degrees C.

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    • "Several porous materials have recently been tested as adsorbent and catalyst substrate for the removal of VOCs from air streams. For example, clay [11], porous polymers [12], zeolite [13] [14], activated carbon [15], alumina [13] [16], SiO 2 [13] [17] [18], Fe 2 O 3 [13], and SnO 2 [19] were commonly used as a support for TiO 2 and other nanoparticles. Among them, Granular activated carbon (GAC) can be a preferred adsorbent and catalyst support. "

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