Matches in SemOpenAlex for { <https://semopenalex.org/work/W2056336724> ?p ?o ?g. }
- W2056336724 endingPage "3725" @default.
- W2056336724 startingPage "3715" @default.
- W2056336724 abstract "Cu(II)/CeO2 catalyst materials have been prepared by two routes, coprecipitation from aqueous solutions containing Cu2+ and Ce4+ ions and sorption of Cu2+ ions on to ceria gel, and their constitutions after thermal treatment in the temperature range 333−1273 K investigated by nitrogen adsorption, powder X-ray diffraction, EPR, and EXAFS. EXAFS data show that the initial Cu(II) species are polymeric Cu(OH)2 and hexaaqua {Cu(H2O)6}2+ ions sorbed onto the surface of the ceria particles from the coprecipitation or impregnation routes, respectively. The materials are mesoporous except after calcination at 1273 K when they become nonporous and crystallites of CuO are apparent. Promotion of ceria with copper(II) enhances the activity toward the oxidation of carbon monoxide dramatically, 100% conversion occurring at 343 K even for high CO concentrations and stoichiometric CO/O2 compositions. The most active catalyst material is formed by thermal processing of materials obtained by either route at ca. 673 K producing a material comprising small particles of ceria on the surface of which copper(II) is dispersed amorphously. EPR shows that, after calcination at 573 K, the copper(II) is present in both types of material as a mixture of isolated Cu2+ ions and amorphous clusters or aggregates of Cu2+ ions. Additionally Cu2+ dimers are formed at 873 K. In situ redox studies show that the amorphous copper(II) aggregates are reduced most easily by exposure to CO at 473 K, followed by the dimer species at 573 K and finally the isolated Cu2+ monomers at 673 K when signals due to Ce3+ appear (i.e. reduction of the support). Reoxidation of all types of Cu+ can be achieved by exposure of the reduced catalyst material to either O2 or NO, although under the same pressure (200 Torr) oxidation by NO is achieved at a lower temperature than with O2. The mode of action of these catalyst materials appears to be synergistic in nature with the principal role of Cu(II) being mainly in electron transfer, abstracting the negative charge remaining when oxygen vacancies are formed following desorption of CO2. The significant enhancement of catalytic activity is due in large part to the efficiency of the Cu(II)/Cu(I) couple in this process. Catalyst deactivation at low temperatures under reducing conditions is due to depletion of the catalyst surface of active oxygen, but activity is restored by treatment in air at moderate temperatures. Deactivation at high temperatures is irreversible and is due to the phase separation of copper(II) oxide coupled with a dramatic increase in particle size." @default.
- W2056336724 created "2016-06-24" @default.
- W2056336724 creator A5023762244 @default.
- W2056336724 creator A5029889316 @default.
- W2056336724 creator A5032853159 @default.
- W2056336724 creator A5063629719 @default.
- W2056336724 creator A5072730899 @default.
- W2056336724 date "2000-11-23" @default.
- W2056336724 modified "2023-09-27" @default.
- W2056336724 title "Nature and Surface Redox Properties of Copper(II)-Promoted Cerium(IV) Oxide CO-Oxidation Catalysts" @default.
- W2056336724 cites W1967173684 @default.
- W2056336724 cites W1967493782 @default.
- W2056336724 cites W1980615022 @default.
- W2056336724 cites W1981934220 @default.
- W2056336724 cites W1988296342 @default.
- W2056336724 cites W2002846392 @default.
- W2056336724 cites W2013319574 @default.
- W2056336724 cites W2020223292 @default.
- W2056336724 cites W2022989493 @default.
- W2056336724 cites W2023618794 @default.
- W2056336724 cites W2060373561 @default.
- W2056336724 cites W2068754430 @default.
- W2056336724 cites W2070738109 @default.
- W2056336724 cites W2075414708 @default.
- W2056336724 cites W2086510372 @default.
- W2056336724 cites W2092585659 @default.
- W2056336724 cites W2114270214 @default.
- W2056336724 cites W2131019860 @default.
- W2056336724 cites W2148984773 @default.
- W2056336724 cites W2241088373 @default.
- W2056336724 doi "https://doi.org/10.1021/cm001113k" @default.
- W2056336724 hasPublicationYear "2000" @default.
- W2056336724 type Work @default.
- W2056336724 sameAs 2056336724 @default.
- W2056336724 citedByCount "153" @default.
- W2056336724 countsByYear W20563367242012 @default.
- W2056336724 countsByYear W20563367242013 @default.
- W2056336724 countsByYear W20563367242014 @default.
- W2056336724 countsByYear W20563367242015 @default.
- W2056336724 countsByYear W20563367242016 @default.
- W2056336724 countsByYear W20563367242017 @default.
- W2056336724 countsByYear W20563367242018 @default.
- W2056336724 countsByYear W20563367242019 @default.
- W2056336724 countsByYear W20563367242020 @default.
- W2056336724 countsByYear W20563367242021 @default.
- W2056336724 countsByYear W20563367242022 @default.
- W2056336724 countsByYear W20563367242023 @default.
- W2056336724 crossrefType "journal-article" @default.
- W2056336724 hasAuthorship W2056336724A5023762244 @default.
- W2056336724 hasAuthorship W2056336724A5029889316 @default.
- W2056336724 hasAuthorship W2056336724A5032853159 @default.
- W2056336724 hasAuthorship W2056336724A5063629719 @default.
- W2056336724 hasAuthorship W2056336724A5072730899 @default.
- W2056336724 hasConcept C107861141 @default.
- W2056336724 hasConcept C119824511 @default.
- W2056336724 hasConcept C121332964 @default.
- W2056336724 hasConcept C161790260 @default.
- W2056336724 hasConcept C178790620 @default.
- W2056336724 hasConcept C179104552 @default.
- W2056336724 hasConcept C185592680 @default.
- W2056336724 hasConcept C187961010 @default.
- W2056336724 hasConcept C192562407 @default.
- W2056336724 hasConcept C28737856 @default.
- W2056336724 hasConcept C46141821 @default.
- W2056336724 hasConcept C544778455 @default.
- W2056336724 hasConcept C55904794 @default.
- W2056336724 hasConcept C56052488 @default.
- W2056336724 hasConcept C62520636 @default.
- W2056336724 hasConcept C7082614 @default.
- W2056336724 hasConcept C8010536 @default.
- W2056336724 hasConcept C82776694 @default.
- W2056336724 hasConceptScore W2056336724C107861141 @default.
- W2056336724 hasConceptScore W2056336724C119824511 @default.
- W2056336724 hasConceptScore W2056336724C121332964 @default.
- W2056336724 hasConceptScore W2056336724C161790260 @default.
- W2056336724 hasConceptScore W2056336724C178790620 @default.
- W2056336724 hasConceptScore W2056336724C179104552 @default.
- W2056336724 hasConceptScore W2056336724C185592680 @default.
- W2056336724 hasConceptScore W2056336724C187961010 @default.
- W2056336724 hasConceptScore W2056336724C192562407 @default.
- W2056336724 hasConceptScore W2056336724C28737856 @default.
- W2056336724 hasConceptScore W2056336724C46141821 @default.
- W2056336724 hasConceptScore W2056336724C544778455 @default.
- W2056336724 hasConceptScore W2056336724C55904794 @default.
- W2056336724 hasConceptScore W2056336724C56052488 @default.
- W2056336724 hasConceptScore W2056336724C62520636 @default.
- W2056336724 hasConceptScore W2056336724C7082614 @default.
- W2056336724 hasConceptScore W2056336724C8010536 @default.
- W2056336724 hasConceptScore W2056336724C82776694 @default.
- W2056336724 hasIssue "12" @default.
- W2056336724 hasLocation W20563367241 @default.
- W2056336724 hasOpenAccess W2056336724 @default.
- W2056336724 hasPrimaryLocation W20563367241 @default.
- W2056336724 hasRelatedWork W1975424802 @default.
- W2056336724 hasRelatedWork W2007976646 @default.
- W2056336724 hasRelatedWork W2029240758 @default.
- W2056336724 hasRelatedWork W2052352729 @default.
- W2056336724 hasRelatedWork W2075525936 @default.