SERS Study of Malachite Green on Silver Nanocaps Arrays

In this paper Ag nanocaps arrays were fabricated with a seed-mediated growth method by depositing Ag films on top of self-assembly close-packed monolayer of SiO2 nanoparticles. Their surface morphologies and optical properties were characterized using TEM, SEM and UV-Vis spectroscopy. Malachite green (MG) was chosen as analyte, the Surface-enhanced Raman Scattering (SERS) spectra of MG adsorbed on Ag nanocaps arrays were investigated. The enhancement factor was estimated to be as large as 4.5x 10(9). These results revealed that these Ag nanostructures are promising for SERS applications in trace measurement and analysis of biological molecules.