Ab initio study of the adsorption properties of CO2 reduction intermediates: The effect of Ni5Ga3 alloy and the Ni5Ga3/ZrO2 interface

Rafael A De Sousa; Vivianne K Ocampo-Restrepo; Lucas G Verga; Juarez L F Da Silva

doi:10.1063/5.0091145

Ab initio study of the adsorption properties of CO₂ reduction intermediates: The effect of Ni₅Ga₃ alloy and the Ni₅Ga₃/ZrO₂ interface

J Chem Phys. 2022 Jun 7;156(21):214106. doi: 10.1063/5.0091145.

Authors

Rafael A De Sousa¹, Vivianne K Ocampo-Restrepo¹, Lucas G Verga¹, Juarez L F Da Silva¹

Affiliation

¹ São Carlos Institute of Chemistry, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, São Paulo, Brazil.

PMID: 35676120
DOI: 10.1063/5.0091145

Abstract

The Ni₅Ga₃ alloy supported on ZrO₂ is a promising catalyst for the reduction of CO₂ due to its higher selectivity to methanol at ambient pressure, e.g., activity comparable to industrial catalysts. However, our atomistic understanding of the role of the cooperative effects induced by the Ni₅Ga₃ alloy formation and its Ni₅Ga₃/ZrO₂ interface in the CO₂ reduction is still far from satisfactory. In this work, we tackle these questions by employing density functional theory calculations to investigate the adsorption properties of key CO₂ reduction intermediates (CO₂, H₂, cis-COOH, trans-COOH, HCOO, CO, HCO, and COH) on Ni₈, Ga₈, Ni₅Ga₃, (ZrO₂)₁₆, and Ni₅Ga₃/(ZrO₂)₁₆. We found that Ni containing clusters tended to assume wetting configurations on the (ZrO₂)₁₆ cluster, while the presence of Ga atoms weakens the adsorption energies on the oxide surface. We also observed that CO₂ was better activated on the metal-oxide interfaces and on the oxide surface, where it was able to form CO₃-like structures. Meanwhile, H₂ activation was only observed on Ni sites, which indicates the importance of distinct adsorption sites that can favor different CO₂ reduction steps. Moreover, the formation of the metal-oxide interface showed to be beneficial for the adsorption of COOH isomers and unfavorable for the adsorption of HCOO.