Synthesis and Characterization of Fe(0.8)Mn(0.2)Fe(2)O(4) Ferrite Nanoparticle with High Saturation Magnetization via the Surfactant Assisted Co-Precipitation.

Manganese ferrite nanoparticles (MnFe(2)O(4)) were synthesized via surfactant-assisted co-precipitation, where sodium dodecyl sulfate (SDS) was used as the template to control particle size at various SDS concentrations. The substitutions of iron (II) (Fe(2+)) into the MnFe(2)O(4) ferrite nanoparticles were carried out to obtain Fe((1)-(x))Mn(x)Fe(2)O(4), with various Mn(2+): Fe(2+) molar ratios. The synthesized ferrite nanoparticles were characterized by the Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TGA), X-ray diffractometer (XRD), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscope (TEM), two-point probe, and vibrating sample magnetometer (VSM) techniques. The experimental Mn:Fe mole ratios of the Fe((1-x))Mn(x)Fe(2)O(4) ferrite nanoparticles were verified to be in agreement with the theoretical values. The synthesized MnFe(2)O(4) and Fe((1-x))Mn(x)Fe(2)O(4) ferrite nanoparticles were of mixed spinel structures, with average spherical particle sizes between 17-22 nm, whereas the magnetite ferrite nanoparticles (Fe(3)O(4)) were of the inverse spinel structure. They showed soft ferromagnetic behavior. The synthesized Fe(0.8)Mn(0.2)Fe(2)O(4) ferrite nanoparticle possessed the highest saturation magnetization of 88 emu/g relative to previously reported work to date.