Synthesis of Sm–Co nanoparticles by sol–gel method

Abstract

Sm–Co nanoparticles have promising applications in both scientific and industrial fields. In this paper, Sm–Co single-crystal nanoparticles were prepared using respective metal salts and complexing agents, such as citric acid by Pechini-type sol–gel method. The mixture solution was heated to form a highly viscous gel, and then heated at different temperatures to achieve SmCo-oxide. And then Sm–Co particles were yielded by reductive annealing of the precursors. Phase analysis, microstructural investigation and magnetic properties were performed by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), Fourier transform infrared (FT-IR) and VSM. TGA trace analysis of the gel determined the heat treatment temperature. XRD results showed that SmCoO3 and Co3O4 were obtained at 800[Formula: see text]C, FT-IR spectrometry analysis also verified the results. In the calcium-thermal reduction process, Sm2O3 and Co were obtained after reductive annealing at 800[Formula: see text]C, meanwhile Sm–Co nanoparticles were formed at 850[Formula: see text]C. FESEM analysis revealed that the Sm–Co nanoparticles were composed in the form of spherical granules and exhibited well distribution with size in the range of 100 nm. The room temperature saturation magnetization and coercivity of the Sm–Co nanoparticles were 49.61 emu/g and 3.53 kOe, respectively.