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 Au₆₀S₆(SCH₂Ph)₃₆ nanoparticle. Single-crystal X-ray crystallography reveals that the as-obtained nanoparticle consists of one Au₁₇ kernel protected by one Au₂₀S₃(SCH₂Ph)₁₈ and one unprecedented Au₂₃S₄(SCH₂Ph)₁₈ motif with the introduced sulfur atom included as a tetrahedral-coordinated μ₄-S. The introduced sulfur leads to the changes of both internal structure and crystallographic arrangement. Unlike the case of 6HLH arrangement in Au₆₀S₆(SCH₂Ph)₃₆ crystals, the “ABAB” arrangement in Au₆₀S₇(SCH₂Ph)₃₆ crystals enhances the solid photoluminescence of amorphous Au₆₀S₇(SCH₂Ph)₃₆ and brings a slight redshift of the maximum emission. The extensive near-infrared emission provides Au₆₀S₇(SCH₂Ph)₃₆ potential applications in some fields such as anticounterfeiting, imaging, etc.