SILVER NANOPARTICLES FILMS DEPOSITED ON AAO TEMPLATES BY THERMAL EVAPORATION FOR SURFACE-ENHANCED RAMAN SCATTERING OF R6G

Abstract

Silver nanoparticles (NPs) films with different nominal thicknesses were deposited on the anodic aluminum oxide (AAO) templates with pore diameter about 200 nm by thermal evaporation. These NPs films were used as the surface enhanced Raman scattering (SERS) active substrates. The microstructure and surface morphology of the films were studied by X-ray diffraction and scanning electron microscopy, respectively. The SERS activity of the films was investigated by Raman scattering of adsorbed rhodamine 6G (R6G) at different concentrations. The results revealed that the average diameter of Ag NPs in different samples is 58 nm, 75 nm, 93 nm and 108 nm, respectively. Ag NPs film on AAO template is very suitable as a SERS active substrate and can detect R6G molecules with a concentration of 10-8 M. The intensity of the SERS spectra is related to both the Ag NPs size and interparticle distance. The sample with an average particle diameter of 93 nm has the highest SERS enhancement factor (1.3 × 106).