Surface-Enhanced Raman Scattering by Hemi-Ellipsoidal Ag Nanoparticles Generated from Silver-Oxide Thin Films

Abstract

By using a focused laser beam, a silver-oxide thin film can be transformed into silver nanoparticles: these form an attractive material for surface-enhanced Raman scattering (SERS). The shape of the nanoparticles was shown to be controllable through changing the thickness of the film, and optimization of the film thickness maximizes the SERS efficiency. A rigorous simulation of optical absorption by Ag nanoparticles proved that the shape of the nanoparticles is tuned to support plasmon resonance at the excitation wavelength used in SERS experiments. The formation of silver nanoparticles is an excellent approach for obtaining cheap, reliable, and efficient SERS substrates.