Preparation iron oxide nanoparticles by coprecipitation method and envestigation the effect of concentraion ratio of reactant on physical and magnetic properties of nanoparticles

Iron oxide nanoparticles were synthesized by coprecipitation method using NaOH as precipitation agent. Magnetic properties of nanoparticles were measured by VSM. The effect of concentration of reactants on the size and magnetic properties of nanoparticles was investigated. The size of particles was calculated by Sherrer formula and magnetic data، and then compared with the size of nanoparticles obtained by TEM. The size of produced nanoparticles ranged from 8 to 12 nanometer and their saturation magnetizations were between 65 to 84 emu/gr. It was found that decrease of concentration ratio of NaOH to iron ions increases the saturation magnetization of nanoparticles significantly، but not their size.