Biosynthesis of Bimetallic Ag-Au (core-shell) Nanoparticles Using Aqueous Extract of Bay Leaves (Laurus nobilis L.)

Abstract

The green synthesis of bimetallic nanoparticles using plant extracts is attracting an increasing attention in the nanoparticle production field since, besides being available for the production of bimetallic nanoparticles, it is cost-effective, eco-friendly, and it is available for large scale production. The required agents to reduce and stabilize metal nanoparticles during synthesis already exist in plant extracts as phytochemicals. The study highlights the synthesis of gold, silver, and silver-gold (bimetallic) nanoparticles at room temperature using an aqueous extract of dried bay leaves and their physical and chemical characterizations for their potential applications. We have synthesized Ag, Au, and Ag-Au nanoparticles using the aqueous bay leaves extract. The nanoparticles were characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). According to UV-Vis spectroscopic results, it is concluded that Ag-Au bimetallic nanoparticles synthesized in the extract have a core-shell arrangement. XRD measurements revealed that all nanoparticles (Ag, Au, and Ag-Au) are in fcc structure. The nanoparticles' average sizes were measured as 10±7, 23±4, and 8±3 nm for Ag, Au, and Ag-Au nanoparticles, respectively, as determined from the TEM images. The results offer that besides Ag and Au nanoparticles, bimetallic Ag-Au nanoparticles synthesized in an aqueous extract of dried bay leaves may play a prominent role in the field of nanotechnology, especially in nanomedicine.