Synthesis of SiO2@Ag Nanocomposite for Investigating Metal-Enhanced Fluorescence and Surface-Enhanced Raman Spectroscopy

Abstract

SiO 2 @Ag nanocomposite (NC) has been synthesized by the chemical reduction and Stӧber method for enhancement photoluminescence (PL) and Raman characteristics of Rhodamine 6G (R6G) and Malachite green (MG) dyes. As-synthesized SiO 2 @Ag nanocomposite indicated SiO 2 nanosphere (NS) and Ag nanoparticle (NP) morphologies. The SiO 2 @Ag nanocomposite was high quality with a wellde ned crystallite phase with average sizes of 24 nm and 132 nm for Ag NP and SiO 2 NC, respectively. By using SiO 2 @Ag NC, the PL intensity of the R6G (at 59.17 ppm) was increased approximately 133 times.The surface-enhanced Raman spectroscopy (SERS) of the MG (at 1.0 ppm) with SiO 2 @Ag NC as substrate, clearly observed vibrational modes in MG dye at 798, 916, 1172, 1394, and 1616 cm − 1 . As a result, the SERS enhancement factor (EF SERS ) at 1172 cm − 1 obtained 6.3x10 6 . This pioneering study points to the potential of SiO 2 @Ag nanocomposite as a promising material for effective photoluminescence and Raman characteristics at low-concentration dyes.