Preparation and Characterization of Ce0_2 @Ag Core/Shell Nanoparticles by Pulsed Laser Ablation in Water

摘要

In this study, we have proposed the first synthesis process of Ce0_2@Ag core/shell nanoparticles NPs by laser ablation in water. The optical and structural properties of Ce0_2@Ag core/shell NPs were characterized using UV-Vis absorption, Fourier transformed infrared FT-IR spectroscopy, x-ray diffraction XRD, scanning electron microscope SEM, energy dispersive x-ray EDX, and transmission electron microscopy TEM. The XRD data confirm the existence of two diffraction peaks related to the crystalline CeO_2 nanoparticles (core) of cubic fluorite phase which highly oriented along (200) plane and the second peak is related to the Ag nanoparticles (shell) of cubic structure. UV-Vis absorption revealed that a sharp absorption peak was observed at 310 nm and the optical energy gap of the synthesized Ce0_2@Ag core/shell NPs was 3.6 eV, while the energy gap of ceria nanoparticles was 3.1 eV. FT-IR results show presence of absorption peak at 550 cm-1, which belonged to Ce-0 stretching mode. TEM investigation shows formation of spherical CeO_2@Ag core/shell with average core size of 35 nm and shell thickness of 15 nm.