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 increasingattention in the nanoparticle production field since, besides being available for the production ofbimetallic 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 plantextracts 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 andchemical characterizations for their potential applications. We have synthesized Ag, Au, and Ag-Aunanoparticles using the aqueous bay leaves extract. The nanoparticles were characterized by UV-Visspectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transforminfrared spectroscopy (FT-IR). According to UV-Vis spectroscopic results, it is concluded that Ag-Aubimetallic nanoparticles synthesized in the extract have a core-shell arrangement. XRD measurementsrevealed that all nanoparticles (Ag, Au, and Ag-Au) are in fcc structure. The nanoparticles' average sizeswere measured as 10±7, 23±4, and 8±3 nm for Ag, Au, and Ag-Au nanoparticles, respectively, asdetermined from the TEM images. The results offer that besides Ag and Au nanoparticles, bimetallic AgAu nanoparticles synthesized in an aqueous extract of