Screened Fe<sub>3</sub> and Ru<sub>3</sub> Single-Cluster Catalysts Anchored on MoS<sub>2</sub> Supports for Selective Hydrogenation of CO<sub>2</sub>
Gang Wang, Xue‐Lian Jiang, Yafei Jiang, Yang‐Gang Wang, Jun Li
Abstract
Efficient CO 2 hydrogenation into valuable products is a promising strategy to address environmental issues and achieve green development goals, yet developing highly active and selective catalysts still remains a major challenge. The single-cluster catalysts frequently exhibit unexpected catalytic performance for complex reactions in heterogeneous catalysis due to the synergistic interaction between the active atoms. In this work, we have proposed candidate catalysts with Fe 3 and Ru 3 clusters anchored at the S vacancies on the MoS 2 substrate for highly selective CO 2 hydrogenation, which is screened from a series of transition-metal clusters including Fe 3, Co 3, Ni 3, Ru 3, Rh 3, and Pd 3 by employing density functional theory calculations. The electron structure analysis reveals that the orbital interactions between metal hydride and CO 2 dominate the adsorption modes of CO 2 molecules on M 3 clusters, wherein CO 2 forms a symmetrical η 1 –C adsorption mode on the Fe 3 cluster and an asymmetric η 2 –C,O adsorption mode on the Ru 3 cluster, thereby leading to different CO 2 hydrogenation pathways. Furthermore, the underlying reaction mechanisms for CO 2 hydrogenation on Fe 3 /MoS 2– v and Ru 3 /MoS 2– v have been explored, and the M 3 clusters are suggested to act as electron reservoirs throughout the whole hydrogenation reaction. Combining with microkinetic simulations, we have showed the highly selective reactivity toward methanol formation on Fe 3 /MoS 2– v and ethanol formation on Ru 3 /MoS 2– v . Our work provides in-depth atomic-scale insights into the mechanism of CO 2 transformation in transition-metal single-cluster catalysis, which would provide ideas for the design and development of highly selective catalysts for CO 2 hydrogenation.