In Situ Depletion-Guided Engineering of Nanoshell-like Gold Nanocluster Assemblies with Enhanced Peroxidase-like Nanozyme Activity

Abstract

Functionalsuperstructures constructed from metal nanoclusters(MNCs) hold great promise in providing highly tunable photoluminescence(PL), catalytic activity, photothermal stability, and biological functionality.However, their controlled synthesis with well-defined size, structure,and properties remains a significant challenge. Herein, we introducea novel approach that combines depletion attraction and thermal activationto induce the in situ formation of spherical superclusters(AuSCs) from Au(I)-thiolate complexes within the assembly. Extensivecharacterization and electron tomographic reconstruction reveal thatAu(I)-thiolate complexes can be sequentially transitioned into metallicAu(0), resulting in hollow nanoshell-like structures withconsistent size (& SIM;110 nm) and diverse shell configurations.Our results demonstrate that AuSCs with thinner shells, containinga high concentration of Au(I)-thiolate complexes, exhibit the highestPL, while AuSCs with thicker shells, containing high concentrationsof metallic gold atoms and low ligand density, show remarkable peroxidase-likenanozyme activity in the 3,3 & PRIME;,5,5 & PRIME;-tetramethylbenzidine(TMB) oxidation reaction.