STUDY ON PREPARATION OF MAGNETIC FLUID BASED ON SYNTHESIZED Fe3O4 MAGNETIC NANOPARTICLES IN WATER AND ORGANIC SOLVENTS

Abstract

Fe₃O₄ magnetic nanoparticles were synthesized by hydrothermal and thermal decomposition methods. Particles synthesized by hydrothermal method were water soluble meanwhile one by thermal decomposition method were organic soluble. Structure, morphology and magnetic properties of magnetic powders and  magnetic fluid samples were characterized. The XRD results pointed out that all of prepared samples had ferrite spinel single phase. The field emission scanning electron microscope (FESEM) and transmission electron microscopy (TEM) images revealed that the as-synthesized nanoparticles were spherical in shape and fairly uniform in size. The mean particle size of the samples synthesized at optimal conditions by hydrothermal method (2 hours, 160 ^oC) and thermal decomposition (2 hours, 300 ^oC) were 15 nm and 13 nm, respectively. The saturation magnetization (M_s) of as high as 63 emu/g and 70 emu/g corresponded to above samples. The magnetic fluid samples were treated with poly(acrylic acid) –PAA as the phase transfer ligand for a high stability with zeta potential values of about -40 to -50 mV. The magnetic fluid system has good dispersion and high stability, which open potential applications in biomedical.