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Structural Evolution of Ga-Cu Model Catalysts for CO₂ Hydrogenation Reactions.

ABSTRACT: We studied the initial stages of Ga interaction with the Cu(001) surface and environment-induced surface transformations in an attempt to elucidate the surface chemistry of the Cu-Ga catalysts recently proposed for CO₂ hydrogenation to methanol. The results show that Ga readily intermixes with Cu upon deposition in vacuum. However, even traces of oxygen in the gas ambient cause Ga oxidation and the formation of two-dimensional ("monolayer") Ga oxide islands uniformly covering the Cu surface. The surface morphology and the oxidized state of Ga remain in H₂ as well as in a CO₂ + H₂ reaction mixture at elevated pressures and temperatures (0.2 mbar, 700 K). The results indicate that the Ga-doped Cu surface under reaction conditions exposes a variety of structures including GaO _x /Cu interfacial sites, which must be taken into account for elucidating the reaction mechanism.

SUBMITTER: Zhong JQ

PROVIDER: S-EPMC7830109 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Structural Evolution of Ga-Cu Model Catalysts for CO2 Hydrogenation Reactions.

Zhong Jian-Qiang JQ Shaikhutdinov Shamil S Roldan Cuenya Beatriz B

The journal of physical chemistry. C, Nanomaterials and interfaces 20210106 2

We studied the initial stages of Ga interaction with the Cu(001) surface and environment-induced surface transformations in an attempt to elucidate the surface chemistry of the Cu-Ga catalysts recently proposed for CO2 hydrogenation to methanol. The results show that Ga readily intermixes with Cu upon deposition in vacuum. However, even traces of oxygen in the gas ambient cause Ga oxidation and the formation of two-dimensional ("monolayer") Ga oxide islands uniformly covering the Cu s ...[more]

PMID: 33510828

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