Surface Structure and Optical Property Modulation of Hybrid‐Peptide‐Capped Gold Nanoclusters and their Aggregation‐Induced Emission Enhancement Behavior

Abstract The impact of the regularity of the surface structure on the intra‐/inter‐particle behavior of luminescent metal nanoclusters (NCs) remains to be unambiguously clarified. Herein, an in‐depth investigation of the relationship between surface structure and the emission pattern of luminescent gold NCs (GNCs) is conducted using a series of NCs coated with opposite‐charged peptides (glutathione [GSH] and poly‐L‐lysine [PLL]) to unravel mutual interactions between ligands and to determine the predominant role of the arrangement of Au(I)‐ligand motifs in respect to their optical properties. GNCs with different emission patterns of 640 nm‐, 820 nm‐, or dual‐emitting are obtained by tuning the adding ratio of PLL to GSH. Moreover, the 640 nm‐emitting GNCs show aggregation‐induced emission enhancement behavior after the introduction of the Pb²⁺ ion, which is used to determine the quantity of Pb²⁺ with a limit of detection as low as 44 nm.