Structural, electronic and catalytic properties of AgnSnn (n=2-14) clusters by density functional theory

Density functional theory (DFT) calculations of clusters were carried out to investigate the structural and electronic properties of AgnSnn (n = 2-14) clusters. Their lowest energy structure, average binding energy, second-order differential energy, HOMO-LUMO energy gap and density of states were analyzed. The reactions of carbon monoxide and oxygen on the Ag-8 cluster and Ag4Sn4 cluster were compared to measure the adsorption and catalytic properties of the Ag4Sn4 cluster. The results show that Ag atoms gather together and are encapsulated by peripheral Sn atoms. The Ag4Sn4 cluster has a magic size. The sp-hybridization plays a crucial role in AgnSnn clusters. For both CO and O-2 adsorption, the effect of the Ag4Sn4 cluster is better than that of the Ag-8 cluster. The addition of an equal proportion of Sn atoms enhanced the catalysis compared to the Ag-8 cluster with the same number of atoms. Our results suggest that the addition of Sn atoms can be an efficient and attractive way of tuning the adsorption ability and reactivity of silver clusters and can provide constructive input for the design of efficient nanocatalysts.

Automated summary

Density functional theory calculations were used to investigate the structural and electronic properties of AgnSnn clusters. It was found that the Ag4Sn4 cluster has a unique magic size and the addition of Sn atoms enhances the catalytic performance of silver clusters.