Developed Ag nanostructures on $c$-Si as surface-enhanced Raman scattering substrates for detection of triphenylmethane dye

Dendritic silver nanostructures on silicon as surface-enhanced Raman scattering substrates are considered in this work. The structures were obtained by chemical reduction of AgNO$_3$ on the silicon surface with different metal deposition time. Positions of “hot spots” of the structures under study was determined qualitatively by means of simulation in COMSOL Multiphysics, and enhancement factors from the structures were calculated $\sim$10$^7$. The surface-enhanced Raman spectroscopy has shown reliable detection of aqueous solution of brilliant green dye on the prepared substrates. Limit of detection of the dye was 10$^{-12}$ M. Using the experimental data, we have determined the enhancement factors reaching 10$^8$ for the least developed structure and 10$^7$ for more developed structures.