| Summary: | <i>L</i>1<sub>0</sub> ordered FePt and FePtCu nanoparticles (NPs) with a good dispersion were successfully fabricated by a simple, green, one-step solid-phase reduction method. Fe (acac)<sub>3</sub>, Pt (acac)<sub>2</sub>, and CuO as the precursors were dispersed in NaCl and annealed at different temperatures with an H<sub>2</sub>-containing atmosphere. As the annealing temperature increased, the chemical order parameter (<i>S</i>), average particle size (<i>D</i>), coercivity (<i>H</i><sub>c</sub>), and saturation magnetization (<i>M</i><sub>s</sub>) of FePt and FePtCu NPs increased and the size distribution range of the particles became wider. The ordered degree, <i>D</i>, <i>H</i><sub>c</sub>, and <i>M</i><sub>s</sub> of FePt NPs were greatly improved by adding 5% Cu. The highest <i>S</i>, <i>D</i>, <i>H</i><sub>c</sub>, and <i>M</i><sub>s</sub> were obtained when FePtCu NPs annealed at 750 °C, which were 0.91, 4.87 nm, 12,200 Oe, and 23.38 emu/g, respectively. The structure and magnetic properties of FePt and FePtCu NPs at different annealing temperatures were investigated and the formation mechanism of FePt and FePtCu NPs were discussed in detail.
|
|---|