Investigating the Dynamics of Pt/CeO2 Catalysts at the Powder Agglomerate Scale by Combining In Situ Hyperspectral Raman Imaging and SEM-EDX Analysis - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue ChemCatChem Année : 2023

Investigating the Dynamics of Pt/CeO2 Catalysts at the Powder Agglomerate Scale by Combining In Situ Hyperspectral Raman Imaging and SEM-EDX Analysis

Résumé

The dynamics of Pt/CeO2 catalysts is a hot topic since its knowledge can be used to (re)generate more active sites for redox reactions, even at low temperature (<500 °C). While numerous works focus on the atomic scale, the spatial extent of Pt surface diffusion is poorly known. In this work, it is evaluated at the powder agglomerate scale using an original methodology combining SEM-EDX analysis and in situ optical/microRaman hyperspectral imaging performed on a Pt/CeO2+CeO2 mechanical mixture. No intergranular diffusion of platinum during redox cycles at 500 °C is revealed by these techniques, in particular by the Raman images of Ce3+ and peroxo species, which are highly sensitive to the presence of Pt atoms. It strongly suggests that Pt surface diffusion takes place only at the nanometer scale and could be limited by atom trapping on Pt/CeO2 agglomerates. Our method for investigating diffusion processes at the micrometer scale may be extended to other thermochemical conditions and other materials.

Domaines

Catalyse
Fichier principal
Vignette du fichier
diffusion Pt_preprint.pdf (482.34 Ko) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Licence : Domaine public

Dates et versions

hal-04220776 , version 1 (16-10-2023)

Identifiants

Citer

C. Molinet-Chinaglia, L. Piccolo, S. Loridant. Investigating the Dynamics of Pt/CeO2 Catalysts at the Powder Agglomerate Scale by Combining In Situ Hyperspectral Raman Imaging and SEM-EDX Analysis. ChemCatChem, 2023, 15 (9), pp.e202300627. ⟨10.1002/cctc.202300627⟩. ⟨hal-04220776⟩
20 Consultations
11 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More