Synthesis and Characteristics of Ag, Cu/Au Core/Shell Nanoparticles Produced by Pulse Laser Ablation

Abstract

Colloidal dispersions of mono Au, Ag , Cu and bimetallic Ag/Au and Cu/Au core/shell nanoparticles are synthesized by pulsed laser ablation of metals targets immersed in 5 ml distilled water (DW). Surface Plasmon resonance (SPR) and particle sizes are characterized by UV-VIS and HRTEM, the X-ray diffraction shows the structure of core/shell. The Surface Plasmon resonance of the produced nanoparticles solutions for silver nanoparticles about 402 nm and copper nanoparticles about 636 nm. While for the core-shell observed two peaks of SPR, Ag/Au core/shell at (406-516) nm, and Cu/Au core/shell observed one peak at 565nm, because the region of gold and copper close together. The shape and particle size have been confirmed by HRTEM measurement, average size is around 12nm for Ag NPs, and 14nm for Cu NPs, while the average size is around 11nm for Ag/Au core/shell NPs and around 13nm for Cu/Au core/shell NPs. Zeta potential (ZP) results proved the silver nanoparticle is more stabilizing (-23.11 mV) than other noble metal nanoparticles,while Ag/Au core/shell is more stabilizing(-27.77mV) with comparison with Cu/Au core/shell which less stabilizing.