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Title: Characterization of Binary Ag-Cu Ion Mixtures in Zeolites: Their Reduction Products and Stability to Air Oxidation

Abstract

A series of Ag+-Cu2+ binary mixtures with different Ag/Cu ratios were supported on mordenite with different Si/Al ratios and were subsequently reduced under hydrogen in the temperature range 323K - 473K. Ag and Cu K-edge X-ray Absorption Spectroscopy (XAS) was conducted on these systems in-situ to monitor the reduction species formed and the kinetics of their reduction. In-situ XANES clearly demonstrates that the formation of silver particles is severely impeded by the addition of copper and that the copper is converted from Cu(II) to Cu(I) during reduction and completely reverts back to Cu(II) during cooling. There are no indications at any stage of the formation of bimetallic Ag-Cu clusters. Interestingly, the Ag/Cu ratio appears to have no influence of the reduction kinetics and reduction products formed with only the highest Si/Al ratio (MR = 128) investigated during this study having an influence on the reduction and stability to air oxidation.

Authors:
 [1];  [2];  [3];  [4]
  1. CCLRC Daresbury Laboratory, Daresbury, Warrington, UK, WA4 4AD (United Kingdom)
  2. CCMC-UNAM, Apdo Postal 2681, 22800 Ensenada. B.C., (Mexico)
  3. Department of Chemistry, University of Southampton, Southampton (United Kingdom)
  4. Laboratorio Ingenieria de Zeolitas, Instituto de Materiales y Reactivos (IMRE) - Universidad de la Habana. Zapata y G. s/n. Havana0400 (Cuba)
Publication Date:
OSTI Identifier:
21054701
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 882; Journal Issue: 1; Conference: XAFS13: 13. international conference on X-ray absorption fine structure, Stanford, CA (United States), 9-14 Jul 2006; Other Information: DOI: 10.1063/1.2644614; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION SPECTROSCOPY; AIR; BINARY MIXTURES; CATALYSTS; COPPER; COPPER IONS; HYDROGEN; INTERFACES; MORDENITE; OXIDATION; PARTICLES; REDUCTION; SILVER; TEMPERATURE DEPENDENCE; X-RAY SPECTROSCOPY

Citation Formats

Fiddy, Steven, Petranovskii, Vitalii, Ogden, Steve, and Iznaga, Inocente Rodriguez. Characterization of Binary Ag-Cu Ion Mixtures in Zeolites: Their Reduction Products and Stability to Air Oxidation. United States: N. p., 2007. Web. doi:10.1063/1.2644614.
Fiddy, Steven, Petranovskii, Vitalii, Ogden, Steve, & Iznaga, Inocente Rodriguez. Characterization of Binary Ag-Cu Ion Mixtures in Zeolites: Their Reduction Products and Stability to Air Oxidation. United States. doi:10.1063/1.2644614.
Fiddy, Steven, Petranovskii, Vitalii, Ogden, Steve, and Iznaga, Inocente Rodriguez. Fri . "Characterization of Binary Ag-Cu Ion Mixtures in Zeolites: Their Reduction Products and Stability to Air Oxidation". United States. doi:10.1063/1.2644614.
@article{osti_21054701,
title = {Characterization of Binary Ag-Cu Ion Mixtures in Zeolites: Their Reduction Products and Stability to Air Oxidation},
author = {Fiddy, Steven and Petranovskii, Vitalii and Ogden, Steve and Iznaga, Inocente Rodriguez},
abstractNote = {A series of Ag+-Cu2+ binary mixtures with different Ag/Cu ratios were supported on mordenite with different Si/Al ratios and were subsequently reduced under hydrogen in the temperature range 323K - 473K. Ag and Cu K-edge X-ray Absorption Spectroscopy (XAS) was conducted on these systems in-situ to monitor the reduction species formed and the kinetics of their reduction. In-situ XANES clearly demonstrates that the formation of silver particles is severely impeded by the addition of copper and that the copper is converted from Cu(II) to Cu(I) during reduction and completely reverts back to Cu(II) during cooling. There are no indications at any stage of the formation of bimetallic Ag-Cu clusters. Interestingly, the Ag/Cu ratio appears to have no influence of the reduction kinetics and reduction products formed with only the highest Si/Al ratio (MR = 128) investigated during this study having an influence on the reduction and stability to air oxidation.},
doi = {10.1063/1.2644614},
journal = {AIP Conference Proceedings},
number = 1,
volume = 882,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
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