Contrasting the Role of Ni/AlO Interfaces in Water-Gas Shift and Dry Reforming of Methane.
Transition metal nanoparticles (NPs) are typically supported on oxides to ensure their stability, which may result in modification of the original NP catalyst reactivity. In a number of cases, this is related to the formation of NP/support interface sites that play a role in catalysis. The metal/sup...
| Publicado en: | Journal of the American Chemical Society Vol. 139; no. 47; pp. 17128 - 17140 |
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| Autores principales: | , , , , , , |
| Formato: | Artículo |
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American Chemical Society
11/29/2017
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| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=126609384&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 126609384 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 11/29/2017 vid: 139 iid: 47 pid: 997 pub: American Chemical Society artinfo: ui: 126609384 10.1021/jacs.7b08984 ppf: 17128 ppct: 12 formats: tig: atl: Contrasting the Role of Ni/AlO Interfaces in Water-Gas Shift and Dry Reforming of Methane. aug: au: Foppa, Lucas Margossian, Tigran Sung Min Kim Muller, Christoph Copßret, Christophe Larmier, Kim Comas-Vives, Aleix affil: Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir Prelog Weg 1-5, CH-8093 Zurich, Switzerland Laboratory of Energy Science and Engineering, Department of Mechanical and Process Engineering, ETH Zurich, Leonhardstrasse 21, CH-8092 Zurich, Switzerland su: Metal nanoparticles Catalysts Chemical reactions Density functional theory Biochemical substrates sug: subj: Metal nanoparticles Catalysts Chemical reactions Density functional theory Biochemical substrates ab: Transition metal nanoparticles (NPs) are typically supported on oxides to ensure their stability, which may result in modification of the original NP catalyst reactivity. In a number of cases, this is related to the formation of NP/support interface sites that play a role in catalysis. The metal/support interface effect verified experimentally is commonly ascribed to stronger reactants adsorption or their facile activation on such sites compared to bare NPs, as indicated by DFT-derived potential energy surfaces (PESs). However, the relevance of specific reaction elementary steps to the overall reaction rate depends on the preferred reaction pathways at reaction conditions, which usually cannot be inferred based solely on PES. Hereby, we use a multiscale (DFT/microkinetic) modeling approach and experiments to investigate the reactivity of the Ni/AlO interface toward water-gas shift (WGS) and dry reforming of methane (DRM), two key industrial reactions with common elementary steps and intermediates, but held at significantly different temperatures: 300 vs 650 °C, respectively. Our model shows that despite the more energetically favorable reaction pathways provided by the Ni/AlO interface, such sites may or may not impact the overall reaction rate depending on reaction conditions: the metal/support interface provides the active site for WGS reaction, acting as a reservoir for oxygenated species, while all Ni surface atoms are active for DRM. This is in contrast to what PESs alone indicate. The different active site requirement for WGS and DRM is confirmed by the experimental evaluation of the activity of a series of AlO-supported Ni NP catalysts with different NP sizes (2-16 nm) toward both reactions. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2017 holdings: @attributes: islocal: N |
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