Size-controlled synthesis of Fe_3O_4 magnetic nanoparticles via an alternating magnetic field and ultrasonic-assisted chemical co-precipitation

摘要

This study aimed to synthesize and develop a new procedure for the production of iron oxide (Fe_3O_4) nanoparticles using three efficient processes. Magnetic Fe_3O_4 nano-powder was simultaneously synthesized by chemical co-precipitation (CCP) method via ultrasonic waves and an alternating magnetic field-assisted. The effect of various agitation factors such as mechanical mixing, magnetic field and ultrasonic pulses was individually studied and then the effect of their binary combination on CCP synthesis investigated and optimized for large scale preparation of magnetite nanoparticles. The influence of KOH as the precipitation agent in different rates on the particle size and their features were studied as well. These magnetic nanoparticles had considerable properties such as an average particle size of 6 nm, lattice parameter of 8.3601 A and optimum saturation magnetization of 57.25 emu/g. The results of various analyses indicated a high degree of crystalline, monophasic Fe nanoparticles of face-centered cubic structure and superparamagnetic behavior.