Surface Single-Atom Tailoring of a Gold Nanoparticle.

Surface single-atom tailoring of a gold nanoparticle, that is, adding, removing, or replacing one surface atom on a structure-resolved nanoparticle in a controlled manner, is very exciting yet challenging and has not been hitherto achieved. Herein we report the first realization of the introduction of a single sulfur atom onto the surface of the structure-unraveled AuS(SCHPh) nanoparticle. Single-crystal X-ray crystallography reveals that the as-obtained nanoparticle consists of one Au kernel protected by one AuS(SCHPh) and one unprecedented AuS(SCHPh) motif with the introduced sulfur atom included as a tetrahedral-coordinated μ-S. The introduced sulfur leads to the changes of both internal structure and crystallographic arrangement. Unlike the case of 6HLH arrangement in AuS(SCHPh) crystals, the "ABAB" arrangement in AuS(SCHPh) crystals enhances the solid photoluminescence of amorphous AuS(SCHPh) and brings a slight redshift of the maximum emission. The extensive near-infrared emission provides AuS(SCHPh) potential applications in some fields such as anticounterfeiting, imaging, etc.