Cu Doping-Induced Transformation from [Ag62S12(SBut)32]2+ to [Ag62−xCuxS12(SBut)32]4+ Nanocluster

The change in the valence state of nanocluster can induce remarkable changes in the properties and structure. However, achieving the valence state changes in nanoclusters is still a challenge. In this work, we use Cu2+ as dopant to "oxidize" [Ag62 S12 (SBut )32 ]2+ (4 free electrons) to obtain the new nanocluster: [Ag62-x Cux S12 (SBut )32 ]4+ with 2 free electrons. As revealed by its structure, the [Ag62-x Cux S12 (SBut )32 ]4+ (x=10∼21) has a similar structure to that of [Ag62 S12 (SBut )32 ]2+ precursor and all the Cu atoms occupy the surface site of nanocluster. It's worth noting that with the Cu atoms doping, the [Ag62-x Cux S12 (SBut )32 ]4+ nanocluster is more stable than [Ag62 S12 (SBut )32 ]2+ at higher temperature and in electrochemical cycle. This result has laid a foundation for the subsequent application and exploration. Overall, this work reveals crystals structure of a new Ag-Cu nanocluster and offers a new insight into the electron reduction/oxidation of nanocluster.