Enhancing SERS Spectra through Surface-Doped Nanocluster Substrates: A Numerical Investigation of Plasmonic Silver Coated Pt and Pd Core–Shell-Satellite Structures

This study numerically investigates the design and function of single bifunctional entities that integrate catalytic activity (Pd/Pt) and Surface-Enhanced Raman Spectroscopy (SERS) activity (Ag). Our approach aims to construct multilayered plasmonic structures with abundant electromagnetic hotspots for sensitive biomolecule detection. By synthesizing complex hybrid metal nanostructures, we aim to overcome limitations in monitoring catalytic reactions, ensuring simultaneous high SERS activity and a large surface area of the catalytically active metal. Utilizing finite-difference time-domain analysis, we evaluate Ag@Pd/Pt@Ag plasmonic core–shell-satellite (PCSS) nanostructures (100 nm core, 2–3 nm shell, 10–30 nm satellites). The pyramidal configuration, featuring a Pd shell demonstrates superior electric field enhancement (approximately 109), offering valuable insights into the synergistic interplay of transition metal nanospacers and satellite nanoclusters in PCSS structures. This study contributes to advancing the understanding of nanotechnology and spectroscopy, aiming to develop robust and cost-effective PCSS nanostructures for reliable sensing applications and theoretical advancements in engineering.