부산대학교 도서관

Among many metal nanoparticles (NPs) with optical properties have attracted attention in various fields because they have their unique surface plasmon resonance (SPR) characteristics. For the past 20 years, nanoparticles have been actively studied with surface-enhanced Raman scattering sensors or surface-enhanced Raman scattering biosensors. In this study, Au NPs, Ag NPs, and Au-Ag alloy NPs were synthesized through aqueous solutions via HAuCl4 and AgNO3, respectively. Ascorbic acid (AA), which is harmless to the human body and is also called vitamin C, was used as the reducing agent, and cethyltrimethylammonium chloride (CTAC) was used as the surfactant. The Au-Ag alloy NPs were added to the surfactant at ratios of 7:3, 5:5, and 3:7, respectively, and then the reducing agent was added to simultaneously reduce gold and silver to synthesize the alloy. The size of the synthesized NPs ranged from 37.3 nm to 180.2 nm, they had spherical and angular shapes. The structural and optical properties of the synthesized nanoparticles were analyzed using UV-vis spectroscopy, transmission electron microscopy (TEM), high resolution-TEM (HR-TEM), high-angle annular dark field scanning TEM (HAADF-STEM), and energy dispersive spectroscopy (EDS). Surface Enhanced Raman Scattering (SERS) characteristics of synthesized NPs were obtained with Benzenethiol (BT) and 2-Mercaptopyridine (2-MP) as analytes. It was confirmed that the SERS intensity of the Au NPs was the highest, followed by the SERS intensity of the Ag NPs. The SERS intensity of Au-Ag alloy NPs tends to be higher as the increases of gold ratio. The synthesized nanoparticles showed different SERS properties depending on their size, shape, and ratio of alloy.