Comparative SERS Activity of Homometallic and Bimetallic Core–Satellite Assemblies

The fabrication of core-satellite (CS) assemblies offers a versatile strategy for tailoring the optical properties of plasmonic nanomaterials. In addition to key factors like size, shape, and spatial arrangement of individual components, the combination of plasmonic units with different compositions (e.g., gold and silver) has been demonstrated to produce materials with enhanced properties and functionalities applicable across a range of fields. Notably, several CS assembly variants have emerged as promising substrates for surface-enhanced Raman spectroscopy (SERS). In this study, we address a gap in the knowledge by conducting a systematic cross-comparison of the optical and SERS properties of highly bright homo- and bimetallic CS assemblies. We evaluated the SERS efficiencies of these different superstructures across various excitation wavelengths and supported our findings with numerical simulations. The insights gained from this study offer a valuable foundation for researchers seeking to select and optimize the most suitable CS assemblies for their given SERS application.