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

The exploration of specific heavy doping of silver atoms into icosahedral Au clusters and their electronic structures and properties has been somewhat limited. Herein, we report two heavily Ag doped nanoclusters, [AuAg(CHNOS)(Dppf)Cl] and [AuAg(CHNOS)(Dppf)Cl](SbF) (AuAg-0 and AuAg-1, respectively) [CHNOSH = 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 AuAg-1 is higher than that of AuAg-0. Transient absorption spectroscopy was performed, revealing that AuAg-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.