| 초록 |
Effect of the shape of nanoporous gold on surface enhanced Raman scattering (SERS) was studied. Cone-shaped nanoporous gold (C-NPG) films were fabricated via nanosphere lithography. A monolayer of polystyrene beads is assembled on an Au/Ag alloy layer. The polystyrene beads are reduced in size using oxygen plasma and directly used as masks for argon ion milling of the underlying Au/Ag alloy layer, which leads to nanocone arrays. C-NPG was obtained after dealloying. The SERS sensitivity is systematically investigated by tuning the shape parameters of C-NPG, including period and height. Compared to conventional nanoporous gold (NPG) films, where the localized surface plasmon resonance (LSPR) at the nanogap in NPG dominates the SERS response, the significantly enhanced SERS response from our C-NPG arises from not only light trapping in the cone-shaped gold nanostructure arrays but also the LSPR at the nanogap in NPG. |
