The active site of ethanol formation from syngas over Cu4 cluster modified MoS2 catalyst: A theoretical investigation

Abstract In order to clarify the active site of Cu4 and MoS2 on the conversion of syngas to ethanol over the Cu4 cluster modified MoS2(0 0 1) [Cu4/MoS2(0 0 1)] surface, we have explored the reaction mechanism of ethanol formation by using density functional theory (DFT) method. It is concluded that CO is first hydrogenated to formyl (CHO) over the Cu4/MoS2 catalyst. The formed CHO is preferentially dissociated to form CH2 by hydrogenation, which is the most favorable CHx monomer. C-C bond is formed by CHO insertion into CH2 leading to the C2 oxygenate CH2CHO, which results in the formation of C2H5OH by successive hydrogenation. The microstructure analysis shows that the Cu4 cluster provides undissociated CO and CHO, while the interface between Cu4 and MoS2 promotes the dissociation of CH2O to form CH2 monomer and promotes the formation of ethanol C-C bond. This work can provide valuable information for the synergistic effect of Cu4 cluster and MoS2 to improve the selectivity of ethanol synthesis.