English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/169578
COMPARTIR / IMPACTO:
Estadísticas
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:
Título

A direct in situ observation of water-enhanced proton conductivity of Eu-doped ZrO2: Effect on WGS reaction

AutorGarcía-Moncada, N.; Bobadilla, L. F.; Poyato, Rosalía ; López-Cartes, C.; Romero-Sarria, F.; Centeno, Miguel Ángel ; Odriozola, José Antonio
Palabras claveSolid Solution
Proton Conductivity
WGS reaction
Eu-doped zirconia
Fecha de publicación2018
EditorElsevier
CitaciónApplied Catalysis B: Environmental 231: 343- 356 (2018)
ResumenEu-doped ZrO solid solutions have been synthesized in order to prepare proton conductors as water-enhancer additives for the WGS reaction. Elemental characterization has been carried out revealing homogeneous dopant distribution resulting in fluorite-type solid solutions for EuO contents up to ∼9 mol.%. Representative samples of the Eu-doped ZrO series have been analysed by Impedance Spectroscopy (IS) in inert, oxygen and wet conditions. The solid solution with 5 mol.% of EuO has presented the highest conductivity values for all tested conditions indicating an optimal amount of dopant. Moreover, the presence of vapour pressure results in an increment of the conductivity at temperatures lower than 300 °C, meanwhile at higher temperatures the conductivity is the same than that in inert conditions. To elucidate these results, in situ DRIFTS studies were carried out. These experiments evidenced the existence of water dissociation at oxygen vacancies (band at 3724 cm) as well as the presence of physisorbed water at temperatures up to ∼300 °C where the band at 5248 cm characteristic of these species disappeared. These results points to a layer model where the physisorbed water interacts with surface hydroxyls generated by dissociated water that improves the proton conductivity through Grotthuss’ mechanism in the RT-300 °C temperature range. These samples were successfully tested in WGS reaction as additive to a typical Pt-based catalyst. The presence of the mixed oxide reveals an increase of the catalyst’ activity assisted by the proton conductor, since improves the water activation step.
URIhttp://hdl.handle.net/10261/169578
Identificadoresdoi: 10.1016/j.apcatb.2018.03.001
issn: 0926-3373
Aparece en las colecciones: (ICMS) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
Accepted Manuscript.pdf Embargado hasta 7 de marzo de 20202,44 MBAdobe PDFVista previa
Visualizar/Abrir     Petición de una copia
Mostrar el registro completo
 

Artículos relacionados:


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.