Synthesis of Fe3O4 Nanoparticles with Different Shapes Through a Co-Precipitation Method and Their Application

Magnetic Fe3O4 nanoparticles (NPs) were successfully synthesized via co-precipitation method using ferric chloride and ferrous sulphate as the starting materials. The shape and the size of Fe3O4 NPs were controlled by using different types of additive including ammonium hydroxide and sodium hydroxide. The results revealed that by adding ammonium hydroxide, the particles attained a spherical shape with a uniform size. On the other hand, the shape of the particles turned from spherical to cubic using sodium hydroxide. The magnetic results showed that both samples attained hysteresis loop, which indicated that both samples have ferromagnetic behavior. In addition, Fe3O4 NPs with cubic shape showed higher adsorptive behaviour towards Congo red compared to spherical Fe3O4 NPs, which is attributed to the enhancement of their magnetic properties. The adsorption of Congo red onto cubic Fe3O4 NPs was best described by Langmuir isotherm model, while spherical Fe3O4 NPs followed Freundlich isotherm model.

Automated summary

This study successfully synthesized magnetic Fe3O4 nanoparticles using co-precipitation method with ferric chloride and ferrous sulphate as starting materials. The shape and size of the nanoparticles were controlled by using different additives. The results showed that spherical nanoparticles with uniform size were obtained when ammonium hydroxide was added, while cubic nanoparticles were obtained with the addition of sodium hydroxide. Both samples exhibited ferromagnetic behavior, but cubic Fe3O4 nanoparticles had higher adsorptive behavior towards Congo red due to enhanced magnetic properties.