Synthesis of CoPt Nanoparticles by Reduction of Co(CH3COO)2 and Pt(acac)2

Abstract

CoPt nanoparticles with an average size of 2.8 – 4.7 nm were synthesized by reduction of non-toxic precursors Co(CH3COO)2and Pt(acac)2using trioctylamine as a solvent at reaction temperature of 260 – 280 °C. The X-ray diffraction pattern showed that as-prepared particles have a disordered face-centered cubic structure while annealing at 700 °C caused them to be an ordered face-centered tetragonal structure. The annealing increased magnetic coercivity of the particles from zero to 772.4 Oe and their saturated magnetization from 15.04 to 27.95 emu/g.