PREPARATION AND INVESTIGATION OF OPTICAL, THERMAL, AND ELECTROCHEMICAL PROPERTIES OF Ag/Co NANOPARTICLES

Abstract

Ag/Co nanoparticles (NPs) were prepared by a two-step method. First, Ag NPs were synthesized by "Controlled Current Coulometry" (CCC) electrochemical method using a Pt rotating electrode. Then, Ag/Co core-shell NPs were prepared through the reduction method using Ag NPs as a core. Both steps were accomplished at room temperature. Techniques such as patterned X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed for the characterization of Ag/Co NPs. Optical properties of synthesized NPs were also investigated by UV-Vis spectroscopy. The absorption peak of Ag NPs was observed at ~400 nm wavelength and the peaks that were detected at 425 nm and 415 nm wavelengths reveal the formation of Ag/Co NPs. The core-shell structure of Ag/Co NPs was confirmed by thermal and electrochemical techniques. We also applied "Mie" theory to calculate the absorption cross-section band of synthesized Ag/Co NPs. Comparison between the results of optical properties and also those obtained from "Mie" theory showed good agreements.