Abstract: Composited nanoparticles, consisting of Mn₃O₄, S-doped Mn₃O₄ and S, were synthesized by co-precipitation reaction and Mn₃O₄ nanoparticles were then obtained after removing the pure S from the composited nanoparticles. The Mn₃O₄-type phase with larger lattice constant a was formed by doping sulfur. At fixed temperatures below Curie temperature (TC), the magnetization of the S-doped Mn₃O₄/S composited nanoparticles was smaller than that of the Mn₃O₄ nanoparticles. The blocking temperature was 36.3 and 34.8 K for S-doped Mn3O4/S composite and Mn₃O₄ nanoparticles, respectively. The anisotropy field of S-doped Mn₃O₄/S composite was determined to be about 55.3 kOe.

Key words: Nanostructured materials, Chemical synthesis, X-ray diffraction, Magnetic measurements