Iron oxides currently attract considerable attention due to their potential applications in the fields of lithiumion batteries, bio-medical sensors, and hyperthermia therapy materials. Magnetite (Fe3O4) is a particularly interesting research target due to its low cost, good biocompatibility, outstanding stability in physiological conditions. Hydrothermal synthesis is one of several liquid-phase synthesis methods with water or an aqueous solution under high pressure and high temperature. This paper reports the growth of magnetic Fe3O4 particles from iron powder (spherical, <10 μm) through an alkaline hydrothermal process under the following conditions: (1) Different KOH molar concentrations and (2) different synthesis time for each KOH molar concentrations. The optimal condition for the synthesis of Fe3O4 using Fe powders is hydrothermal oxidation with 6.25 M KOH for 48 h, resulting in 89.2 emu/g of saturation magnetization at room temperature. The structure and morphologies of the synthesized particles are characterized by X-ray diffraction (XRD, 2θ = 20°–80°) with Cu-kα radiation and field emission scanning electron microscopy (FE-SEM), respectively. The magnetic properties of magnetite samples are investigated using a vibrating sample magnetometer (VSM). The role of KOH in the formation of magnetite octahedron is observed.

Abstract
1. 서 론
2. 실 험
3. 결과 및 토의
4. 결 론
References

• 이기범(한남대학교 광전자물리학과) | Ki-Bum Lee (Department of Applied Physics, Hannam University)
• 남충희(한남대학교 광전자물리학과/한남대학교 전기전자공학과) | Chunghee Nam (Department of Applied Physics, Hannam University/Department of Electrical and Electronic Engineering, Hannam University) Corresponding Author