Synthesis of Sm–Co and Sm–Co/Fe nanocrystals by reductive annealing of nanoparticles

▶ Preparation of SmCo 5/Sm 2Co 17 nanocrystals and SmCo 5/Fe nanocomposite using bottom up approach. ▶ Composition of the compound can be control by varying initial molar ratio of metal precursors. ▶ Increasing Fe fraction in SmCo 5/Fe composite has resulted in deceasing coercivity and an increasing in saturation magnetization. ▶ The synthesis procedure is easily scalable for large scale production. We report here a simple route for the chemical synthesis of SmCo 5 and Sm 2Co 17 single-phase and SmCo 5/Fe composite nanocrystals by polyol reduction of metal precursors and subsequent calcium reductive annealing. Sm 2O 3 and Co nanoparticles were synthesized first, and nanocrystalline SmCo 5 or Sm 2Co 17, compound with tunable composition was then obtained after the annealing. The composition of the compound was controlled by varying the initial molar ratio of the metal precursors. At room temperature, the obtained SmCo 5 and Sm 2Co 17 show coercivity of 12 kOe and 4 kOe, and saturation magnetization of 70 emu/g and 85 emu/g, respectively. To prepare SmCo 5/Fe nanocomposites, Fe, Co and Sm 2O 3 nanoparticles were synthesized in one-pot by polyol reduction of the metal precursors.