Fabrication of a family of atomically precise silver nanoclusters via dual-level kinetic control.

The controllable preparation of metal nanoclusters in high yield is an essential prerequisite for their fundamental research and extensive application. Here a synthetic approach termed "dual-level kinetic control" was developed to fabricate a family of new silver nanoclusters. The introduction of secondary ligands was first exploited to retard the reduction rate and accomplish the first-level kinetic control. And the cooling of the reaction was performed to further slow the reduction down and accomplish the second-level kinetic control. A family of atomically precise silver nanoclusters (including [Ag 25 (SR) 18 ] - , [Ag 34 (SR) 18 (DPPP) 3 Cl 4 ] 2+ , [Ag 36 (SR) 26 S 4 ] 2+ , [Ag 37 (SR) 25 Cl 1 ] + , and [Ag 52 (SR) 28 Cl 4 ] 2+ ) were controllably prepared and structurally determined. The developed "dual-level kinetic control" hopefully acts as a powerful synthetic tool to manufacture more nanoclusters with unprecedented compositions, structures, and properties.