Gold Nanocluster-Silver Nanoparticle-MoS₂ Heterostructures as SERS-Active Catalysts With Enhanced Electron-Donating Capability.

Metal nanoclusters (MNCs)-semiconductor (SC) composite materials have garnered significant attention due to the fascinating and versatile properties exhibited by MNCs. However, there is a scarcity of efforts directed toward incorporating metal nanoparticles (MNPs) into MNCs-SC composites to facilitate charge generation within the system. And the underlying mechanism governing charge transfer in such systems remains elusive. In this work, a straightforward reduction-adsorption strategy was employed to ingeniously introduce AuNCs into the AgNPs@MoS₂ binary nanostructure. This approach effectively improves the electron-donating performance of resulting AuNCs-AgNPs@MoS₂ ternary heterostructures, which were utilized as the substrates for SERS-active p-nitrothiophenol (PNTP)-catalytic reactions. PNTP-catalytic experiments further validated the enhanced catalytic performance arising from the introduction of AuNCs into the ternary heterostructure. Furthermore, the composite mechanism of AuNCs and AgNPs in the nanosystem was elucidated, revealing that AgNPs act as charge bridges and synergistically facilitate charge generation in conjunction with AuNCs. The electron-donating capability was quantified using the concept of charge transfer degree, rendering the impact of AuNCs incorporation on charge yield more intuitive. This study is anticipated to provide a rational approach for the construction of MNCs-MNPs@SC ternary nanostructures and optimizing the synergistic interaction between MNCs and MNPs, thereby enabling their applications across diverse fields.