Abstract:

Objectives The catalytic hydrogenation of CO₂ to methanol is one of the effective approaches for CO₂ emission reduction. Metal-doped graphene is a potential catalyst for CO₂ hydrogenation. To support the design and development of catalysts, the mechanism of CO₂ hydrogenation catalyzed by Mo-doped graphene (Mo-graphene) is investigated. Methods Density functional theory (DFT) calculations and electronic structure analysis methods are used to study the catalytic activity of Mo-graphene, CO₂ adsorption, and the reaction pathway for methanol production methanol production via hydrogenation. Results Mo doping improves the catalytic activity of the graphene-based catalyst. The optimal adsorption configuration of CO₂ on the catalyst is co-adsorption of carbon and oxygen. The adsorbed CO₂ initially tends to bond with C and H, generating the key intermediate HCOO. The formation of HCOOH is identified as the rate-determining step in CO₂ reduction. The corresponding reaction pathway is: CO₂→_{HCOO→HCOOH→HCO→H2CO→H3CO→CH3OH. Conclusions Mo doping can improve the selectivity of the CO2 hydrogenation pathway on graphene-based catalysts, which is conducive to enhancing the selectivity of methanol.}

Key words: carbon capture, carbon emission, graphene, Mo doping, CO₂ hydrogenation, methanol