Magnetic and structural properties of L10 FePt/MnFe2O4 nanotomposites

Monodispersed 4.1 nm FePt nanoparticles were successfully synthesized by the chemical polyol process with co-reduction of iron acetylacetonate, Fe(acac)3 and platinum acetylacetonate, Pt(acac)(2). High temperature (usually higher than 550 degrees C) annealing is necessary to obtain L1(0) ordered structure. The agglomeration of particles takes place during post-annealing process. In the present work, we prevent sintering of FePt nanoparticles during the annealing process at temperatures of 750 and 850 degrees C by using nanocomposite structure. In this case, MnFe2O4 nanoparticles were used successfully to preserve particles from sintering. The results show a decrease in coercivity by adding MnFe2O4 in nanocomposite. This might be due to the effective exchange coupling happens between FePt and MnFe2O4 parts. Furthermore, the well isolated L1(0) FePt nanoparticles with coercivity of 4300 Oe are prepared and magnetic properties of L1(0) FePt MnFe2O4 nanocomposite are studied. (c) 2014 Elsevier Ltd. All rights reserved.