MoS 2 -supported Au 31 for CO hydrogenation: A first-principle study

Jiang, Tao; Le, Duy; Rahman, Talat S.

doi:10.1116/1.5142853

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MoS 2 -supported Au 31 for CO hydrogenation: A first-principle study

Jiang, Tao·Le, Duy·Rahman, Talat S.

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Abstract

While the basal plane of single-layer molybdenum disulphide (MoS 2 ) is inert, attempts have been made to functionalize it chemically through the creation of defects and/or addition of dopants. With nanoparticles as dopants, the authors present density functional theory-based calculations of the hydrogenation of CO on a 31-atom, bilayer Au cluster supported on single-layer MoS 2 (Au31/MoS 2 ). Not surprisingly, the adsorption and reaction of all species involved in the hydrogenation occur at the edges of the cluster—the regions at which the interaction between MoS 2 and the Au cluster is tracked to be the strongest. The authors find two possible mechanisms that lead to the formation of methanol: (1) CO* → CHO* → CH 2 O* → CH 3 O* → CH 3 OH* and (2) CO* → CHO* → HCOH* → CH2OH* → CH3OH*, where * indicates the adsorbed species. Detailed analysis of the reaction pathways, however, does not result in favoring one mechanism over the other. Rather, both mechanisms are facile. In addition, the rate-limiting step in each mechanism is found to be the formation of the formyl radical group (CO* + H* → CHO*).

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2D materials 36 MATERIALS SCIENCE Adsorption Crystal structure Density functional theory First-principle calculations Hydrogenation process Materials Science Nanoparticles Physics Reaction mechanisms Syngas Transition metal chalcogenides

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Jiang, Tao, Le, Duy, Rahman, Talat S.. 2020-05-01. MoS 2 -supported Au 31 for CO hydrogenation: A first-principle study. https://doi.org/10.1116/1.5142853

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