Figueras, MarcGutiérrez, Ramon A.Viñes Solana, FrancescRamirez, Pedro J.Rodríguez, José A.Illas i Riera, Francesc2023-03-102023-03-102021-08-062155-5435https://hdl.handle.net/2445/194996Experiments under controlled conditions show that MoCx nanoclusters supported on an inert Au(111) support are efficient catalysts for CO2 conversion, although with a prominent role of stoichiometry. In particular, C-deficient nanoparticles directly dissociate CO2 and rapidly become deactivated. On the contrary, nearly stoichiometric nanoparticles reversibly adsorb/desorb CO2 and, after exposure to hydrogen, CO2 converts predominantly to CO with a significant amount of methanol and no methane or other alkanes as reaction products. The apparent activation energy for this process (14 kcal/mol) is smaller than that corresponding to bulk δ-MoC (17 kcal/mol) or a Cu(111) benchmark system (25 kcal/mol). This trend reflects the superior ability of MoC1.1/Au(111) to bind and dissociate CO2. Model calculations carried out in the framework of density functional theory provide insights into the underlying mechanism suggesting that CO2 hydrogenation on the hydrogen-covered stoichiometric MoCx nanoparticles supported on Au(111) proceeds mostly under an Eley-Rideal mechanism. The influence of the Au(111) is also analyzed and proven to have a role on the final reaction energy but almost no effect on the activation energy and transition state structure of the analyzed reaction pathways.9 p.application/pdfengcc-by (c) Figueras, Marc, et al., 2021http://creativecommons.org/licenses/by/3.0/es/HidrogenacióCompostos de carboniDissociació (Química)HydrogenationCarbon compoundsDissociationinfo:eu-repo/semantics/article7139362023-03-10info:eu-repo/semantics/openAccess