Surface-enhanced Raman scattering on nanoporous Au

Kucheyev SO, Hayes JR, Biener J, Huser T, Talley CE, Hamza AV. Surface-enhanced Raman scattering on nanoporous Au. Applied Physics Letters. 2006;89(5):053102.Colloidal solutions of metal nanoparticles are currently among the most studied substrates for sensors based on surface-enhanced Raman scattering (SERS). However, such substrates often suffer from not being cost-effective, reusable, or stable. Here, we develop nanoporous Au as a highly active, tunable, stable, biocompatible, and reusable SERS substrate. Nanoporous Au is prepared by a facile process of free corrosion of AgAu alloys followed by annealing. Results show that nanofoams with average pore widths of similar to 250 nm exhibit the largest SERS signal for 632.8 nm excitation. This is attributed to the electromagnetic SERS enhancement mechanism with additional field localization within pores. (c) 2006 American Institute of Physics