Improved Surface-Enhanced Raman Scattering Performances on Silver-Silica Nanocomposites

In this work, surface-enhanced Raman scattering (SERS)-active silver substrates were prepared by electrochemical methods via oxidation-reduction cycles. These SERS-active substrates were further modified with different contents of SiO(2) nanoparticles to improve their corresponding SERS performances. With the modified substrate prepared in a 0.1 nM SiO(2) Solution, the SERS of Rhodamine 6G (R6G) exhibits a higher intensity by a 3-fold order of magnitude as compared with that of R6G adsorbed on a SERS-active Ag substrate without the incorporation of SiO(2) nanoparticles. Moreover, the modified substrate prepared in a 1 mM SiO(2) solution can improve the thermal stability of the SERS-active Ag substrate. The operation temperature of the modified Ag substrate can be raised by 50 degrees C. The aging SERS intensity is also depressed on this modified Ag substrate due to the contribution of SiO(2) nanoparticles to SERS effects.