Synthesis of carbon-encapsulated magnetic nanoparticles by pulsed laser irradiation of solution

Abstract

A method for synthesizing carbon -encapsulated magnetic nanoparticles (CEMNPs) is reported. In the proposed method, a solution containing various metalocenes dissolved in xylene is irradiated with a nanosecond pulsed ultraviolet laser at room temperature and atmospheric pressure. Upon the completion of irradiation, CEMNPs (Fe-C, Ni-C, Co-C) with diameters ranging from a few nanometers to about 300 nm are produced in the solution. The material characteristics of these nanoparticles are then examined with electron microscopy, Raman spectroscopy, X-ray diffraction (XRD) and superconducting quantum interference device (SQUID) magnetometry It was found that the magnetic nanoparticles coated with graphitic shells exhibit good stability in a high concentration HCl (10 mol) solution. The possible growth mechanisms of CEMNPs under the pulsed laser irradiation of the solution are then discussed. (C) 2008 Elsevier Ltd. All rights reserved.