Elucidating the Role of the Metal Catalyst and Oxide Support in the Ru/CeO₂-Catalyzed CO₂ Methanation Mechanism.

ABSTRACT: This study addresses the yet unresolved CO₂ methanation mechanism on a Ru/CeO₂ catalyst by means of near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) complemented with periodic density functional theory (DFT) calculations. NAP-XPS results show that the switch from H₂ to CO₂ + H₂ mixture oxidizes both the Ru and CeO₂ phases at low temperatures, which is explained by the CO₂ adsorption modes assessed by means of DFT on each representative surface. CO₂ adsorption on Ru is dissociative and moderately endergonic, leading to polybonded Ru-carbonyl groups whose hydrogenation is the rate-determining step in the overall proce

SUBMITTER: Lopez-Rodriguez S 

PROVIDER: S-EPMC8631708 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature