dc.contributor.author | Kalamaras, Christos M. | en |
dc.contributor.author | Dionysiou, Dionysios Demetriou D. | en |
dc.contributor.author | Efstathiou, Angelos M. | en |
dc.creator | Kalamaras, Christos M. | en |
dc.creator | Dionysiou, Dionysios Demetriou D. | en |
dc.creator | Efstathiou, Angelos M. | en |
dc.date.accessioned | 2019-11-21T06:19:35Z | |
dc.date.available | 2019-11-21T06:19:35Z | |
dc.date.issued | 2012 | |
dc.identifier.issn | 2155-5435 | |
dc.identifier.uri | http://gnosis.library.ucy.ac.cy/handle/7/55601 | |
dc.description.abstract | A series of y wt % Pt/CexZr1-xO2 catalysts (y = 0.1, 0.5, and 1.0 | en |
dc.description.abstract | x = 0.3, 0.5, and 0.7) were synthesized and characterized to investigate the effect of CeO2 doping with Zr 4+ and of Pt particle size (Pt/Ce0.5Zr0.5O 2) on important mechanistic and kinetic aspects of the water-gas shift (WGS) reaction. These included the concentration (μmol·g -1 or θ (surface coverage based on Pts)) and chemical structure of active reaction intermediates present in the "carbon path" and "hydrogen path" of the WGS reaction in the 200-300 °C range and the prevailing mechanism among "redox" and "associative formate" largely considered in the literature. Toward this goal, steady-state isotopic transient kinetic analysis coupled with in situ DRIFTS and mass spectrometry experiments were performed for the first time using D2O and 13CO isotopic gases. A novel transient isotopic experiment allowed quantification of the initial transient rate of reaction of adsorbed formate (HCOO-) with water and that of adsorbed CO with water under steady-state WGS reaction conditions. On the basis of these results, it was concluded that formate should not be considered as an important intermediate. It was found that on Pt/CexZr1-xO 2 catalysts, the WGS reaction mechanism switches from "redox" to a combination of "redox" and "associative formate with -OH group regeneration" mechanisms by increasing the reaction temperature from 200 to 300 °C. The superior WGS activity exhibited by Pt/CexZr1-xO2 (x = 0.3, 0.5, and 0.7) catalysts in comparison with Pt/CeO2 was explained by the fact that the site reactivity of Pt across the metal-support interface was increased as a consequence of the introduction of Zr4+ into the ceria lattice. The concentration of active reaction intermediates was found to strongly depend on reaction temperature, support composition (Ce/Zr ratio), and Pt particle size, parameters that all determine the shape of the light-off CO-conversion curve. © 2012 American Chemical Society. | en |
dc.source | ACS Catalysis | en |
dc.source.uri | https://www.scopus.com/inward/record.uri?eid=2-s2.0-84870887116&doi=10.1021%2fcs3006204&partnerID=40&md5=bf849f9cfe8302c244ba79661693c556 | |
dc.subject | Platinum | en |
dc.subject | Experiments | en |
dc.subject | Hydrogen | en |
dc.subject | Mass spectrometry | en |
dc.subject | Particle size | en |
dc.subject | Zirconium | en |
dc.subject | Cerium compounds | en |
dc.subject | Catalyst activity | en |
dc.subject | Isotopes | en |
dc.subject | Catalyst regeneration | en |
dc.subject | Water gas shift | en |
dc.subject | WGS reactions | en |
dc.subject | Reaction intermediates | en |
dc.subject | SSITKA-DRIFTS | en |
dc.subject | SSITKA-MS | en |
dc.subject | WGS reaction mechanism | en |
dc.subject | ceria-zirconia | en |
dc.subject | supported Pt | en |
dc.subject | transient isotopic techniques | en |
dc.title | Mechanistic studies of the water-gas shift reaction over Pt/Ce xZr1-xO2 catalysts: The effect of Pt particle size and Zr Dopant | en |
dc.type | info:eu-repo/semantics/article | |
dc.identifier.doi | 10.1021/cs3006204 | |
dc.description.volume | 2 | |
dc.description.issue | 12 | |
dc.description.startingpage | 2729 | |
dc.description.endingpage | 2742 | |
dc.author.faculty | 002 Σχολή Θετικών και Εφαρμοσμένων Επιστημών / Faculty of Pure and Applied Sciences | |
dc.author.department | Τμήμα Χημείας / Department of Chemistry | |
dc.type.uhtype | Article | en |
dc.description.notes | <p>Cited By :64</p> | en |
dc.source.abbreviation | ACS Catal. | en |
dc.contributor.orcid | Efstathiou, Angelos M. [0000-0001-8393-8800] | |
dc.contributor.orcid | Kalamaras, Christos M. [0000-0001-6809-5948] | |
dc.gnosis.orcid | 0000-0001-8393-8800 | |
dc.gnosis.orcid | 0000-0001-6809-5948 | |