کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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62025 | 47617 | 2010 | 12 صفحه PDF | دانلود رایگان |
A series of silica-supported Pt, Ru, and Pt–Ru catalysts has been synthesized using dendrimer–metal nanocomposite (DMN) precursors prepared by both co- and sequential complexation with metal salts. The catalysts have been characterized by several techniques, including electron microscopy, temperature-programmed titration of adsorbed oxygen, and X-ray diffraction. Liquid-phase selective hydrogenation of 3,4-epoxy-1-butene (EpB) was used as a probe reaction to evaluate their catalytic performance. The bimetallic catalyst prepared by the co-complexation method exhibits a superior catalytic activity compared to the sequential one, and is much more active than a conventional catalyst prepared by incipient wetness. The activity enhancement is attributed to a bifunctional performance of the PtRu alloy sites created, based on a strong correlation between turnover frequencies, and both the alloy compositions and metal surface site distributions. In addition, the co-complexation catalyst is selective toward crotonaldehyde, suggesting that this reaction pathway is favored on the PtRu sites.
Pt–Ru dendrimer-metal nanocomposites were synthesized using co-complexation and sequential complexation methods as shown. The Pt–Ru bimetallic catalysts synthesized via dendrimer route were found to exhibit different structural properties and catalytic performance (i.e., activities, selectivities) for selective hydrogenation when compared to conventionally prepared Pt–Ru samples.Figure optionsDownload high-quality image (166 K)Download as PowerPoint slide
Journal: Journal of Catalysis - Volume 269, Issue 2, 5 February 2010, Pages 376–387