{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Baumgartner JF"],"funding":["Swiss National Science Foundation"],"pagination":["4871-4880"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC10966962"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["15(13)"],"pubmed_abstract":["Supported bimetallic nanoparticles (NPs) often display improved catalytic performances (activity and/or selectivity). Yet, structure-activity relationships are difficult to derive due to the multitude of possible compositions, interfaces and alloys. This is notably true for bimetallic NPs used in the selective hydrogenation of CO<sub>2</sub> to methanol, where the NPs respond dynamically to the chemical potential of the reactants and products. Herein, we use a combined computational and experimental approach that leverages <i>ab initio</i> Molecular Dynamics (AIMD) and Metadynamics (MTD) in conjunction with <i>in situ</i> X-ray absorption spectroscopy, chemisorption and CO-IR, to explore the dynamic structures and interactions with adsorbates under various CO<sub>2</sub> hydrogenation conditions in highly active and selective silica-supported PdGa NPs. We find that PdGa alloying generates isolated Pd sites at the NP surface, changing the dominant binding modes of relevant adsorbates compared to pure Pd NPs: CO molecules mainly occupy atop sites and hydrides switch from mainly internal to atop and bridge sites. Under more oxidizing conditions, akin to CO<sub>2</sub> hydrogenation, Ga is partially oxidized, forming a GaO<sub><i>X</i></sub> layer on the NP surface, with a partially dealloyed PdGa core and some remaining isolated Pd surface sites. Overall, these bimetallic NPs show high structural dynamics and a variable extent of alloying depending on the adsorbates relevant to CO<sub>2</sub> hydrogenation. This work highlights that AIMD/MTD is a powerful approach to elucidate structural dynamics at a single particle level in complex catalytic systems."],"journal":["Chemical science"],"pubmed_title":["Metadynamics simulations reveal alloying-dealloying processes for bimetallic PdGa nanoparticles under CO<sub>2</sub> hydrogenation."],"pmcid":["PMC10966962"],"funding_grant_id":["200021","183495","169134"],"pubmed_authors":["Comas-Vives A","Baumgartner JF","Muller A","Payard PA","Coperet C","Docherty SR"],"additional_accession":[]},"is_claimable":false,"name":"Metadynamics simulations reveal alloying-dealloying processes for bimetallic PdGa nanoparticles under CO<sub>2</sub> hydrogenation.","description":"Supported bimetallic nanoparticles (NPs) often display improved catalytic performances (activity and/or selectivity). Yet, structure-activity relationships are difficult to derive due to the multitude of possible compositions, interfaces and alloys. This is notably true for bimetallic NPs used in the selective hydrogenation of CO<sub>2</sub> to methanol, where the NPs respond dynamically to the chemical potential of the reactants and products. Herein, we use a combined computational and experimental approach that leverages <i>ab initio</i> Molecular Dynamics (AIMD) and Metadynamics (MTD) in conjunction with <i>in situ</i> X-ray absorption spectroscopy, chemisorption and CO-IR, to explore the dynamic structures and interactions with adsorbates under various CO<sub>2</sub> hydrogenation conditions in highly active and selective silica-supported PdGa NPs. We find that PdGa alloying generates isolated Pd sites at the NP surface, changing the dominant binding modes of relevant adsorbates compared to pure Pd NPs: CO molecules mainly occupy atop sites and hydrides switch from mainly internal to atop and bridge sites. Under more oxidizing conditions, akin to CO<sub>2</sub> hydrogenation, Ga is partially oxidized, forming a GaO<sub><i>X</i></sub> layer on the NP surface, with a partially dealloyed PdGa core and some remaining isolated Pd surface sites. Overall, these bimetallic NPs show high structural dynamics and a variable extent of alloying depending on the adsorbates relevant to CO<sub>2</sub> hydrogenation. This work highlights that AIMD/MTD is a powerful approach to elucidate structural dynamics at a single particle level in complex catalytic systems.","dates":{"release":"2024-01-01T00:00:00Z","publication":"2024 Mar","modification":"2025-04-04T23:52:56.86Z","creation":"2025-04-04T23:52:56.86Z"},"accession":"S-EPMC10966962","cross_references":{"pubmed":["38550689"],"doi":["10.1039/d4sc00484a"]}}