Effect of Specific Heavy Doping of Silver Atoms into the Icosahedral Au13 on Electronic Structure and Catalytic Performance

The exploration of specific heavy doping of silver atoms into icosahedral Au13 clusters and their electronic structures and properties has been somewhat limited. Herein, we report two heavily Ag doped nanoclusters, [Au7Ag6(C7H4NOS)4(Dppf)3Cl]0 and [Au7Ag6(C7H4NOS)3(Dppf)3Cl](SbF6) (Au7Ag6-0 and Au7Ag6-1, respectively) [C7H4NOSH = 2-mercaptobenzoxazole, and Dppf = 1,1'-bis(diphenylphosphino)ferrocene]. The electronic structures and superatomic orbitals of nanoclusters were determined by density functional theory (DFT) calculations, and the energy degeneracy of the superatomic orbitals of Au7Ag6-1 is higher than that of Au7Ag6-0. Transient absorption spectroscopy was performed, revealing that Au7Ag6-0 significantly extends the excited-state lifetime. Both nanoclusters were supported on activated carbon for the oxygen reduction reaction. DFT calculations confirm that the catalytic activities mainly stem from the carbon atom of ferrocene rather than the iron atom. This study not only sheds light on the preparation of icosahedral alloy clusters but also provides insights into the regulation of icosahedral superatomic structure and electrocatalytic properties.