Synthesis and magnetic properties of multifunctional CoPtAu nanoparticles

Abstract

We present the synthesis and magnetic properties of multifunctional CoPtAu alloy nanoparticles of three compositions, Co0.33Pt0.33Au0.33, Co0.2Pt0.2Au0.6, and Co0.4Pt0.4Au0.2, by a modified polyol process. The x-ray diffraction and transmission electron microscopy analyses confirm the formation of the alloy nanostructure comprising Au-rich and Pt-rich nanophases, with a narrow distribution of particle sizes and provides the detailed structural arrangements. The magnetic study shows the composition dependence of the magnetic properties of the nanoparticles, from superparamagnetic for both Co0.33Pt0.33Au0.33 and Co0.4Pt0.4Au0.2 to soft ferromagnetic for Co0.2Pt0.2Au0.6. (c) 2009 American Institute of Physics. [DOI: 10.1063/1.3072750]