Cd-driven surface reconstruction and photodynamics in gold nanoclusters

Abstract

With atomically precise gold nanoclusters acting as a starting unit, substituting one or more gold atoms of the nanocluster with other metals has become an effective strategy to create metal synergy for improving catalytic performances and other properties. However, so far detailed insight into how to design the gold-based nanoclusters to optimize the synergy is still lacking, as atomic-level exchange between the surface-gold (or core-gold) and the incoming heteroatoms is quite challenging without changing other parts. Here we report a Cd-driven reconstruction of Au₄₄(DMBT)₂₈ (DMBT = 3,5-dimethylbenzenethiol), in which four Au₂(DMBT)₃ staples are precisely replaced by two Au₅Cd₂(DMBT)₁₂ staples to form Au₃₈Cd₄(DMBT)₃₀ with the face-centered cubic inner core retained. With the dual modifications of the surface and electronic structure, the Au₃₈Cd₄(DMBT)₃₀ nanocluster exhibits distinct excitonic behaviors and superior photocatalytic performances compared to the parent Au₄₄(DMBT)₂₈ nanocluster.