Studies of Fe<sub>3</sub>O<sub>4</sub> Nanoparticles Prepared by Co-Precipitation Method of FeSO<sub>4</sub> and FeCl<sub>3</sub> Solution

The magnetic properties of magnetite nanoparticles (Fe 3 O 4 NPs) are being investigated. Fe 3 O 4 NPs were prepared using the co-precipitation method and oven dried. The magnetic properties are influenced by the electron environments of the Fe 3+ ions within the iron oxide structure. XPS spectra of Fe 3+ (2p 3/2 ) and (2p 1/2 ) show peaks around 706.45 eV and 720.76 eV, respectively. Furthermore, magnetite NPs dried at 60 °C exhibited the largest hysteresis loop at 50K and less at 300K. In addition, the values of Ms and Mr indicate ferromagnetic behavior in Fe 3 O 4 NPs. The result of this material shows high Ms (~38.638 emu/g) at 50K with Hc of 3.094K (near ferromagnetism) and ~33.843 emu/g at 300K with Hc of 0.000K (superparamagnetic). However, these magnetic properties are utilized for biomaterial applications such as separating biomolecules or coating core shells for nanoparticles, which presents an option for future biomedical technology.