SERS substrates of Ag nanoparticles decorated Si nanostage with neck for Thiram detection

Nanosphere lithography enables tunable fabrication of Si nanoarrays (hexagons, stages, cones) on Si (100) by precisely controlling etching time. Specifically, the nanostage arrays, with their high surface area due to neck regions, can absorb more Ag nanoparticles (AgNPs), leading to superior SERS performance through the formation of hotspots. In addition, COMSOL simulations confirm plasmon coupling inter-particle, particle-film, and inter-structure. The linear detection of Thiram (0.05–50 ppm) remains stable within 120 days, meeting practical requirements for pesticide detection and showing potential for food safety applications.