Fatima Hira, Lee Dae-Won, Yun Hyun Joong, Kim Kyo-Seon
Department of Chemical Engineering, Kangwon National University Chuncheon Kangwon-Do 200-701 Korea
RSC Adv. 2018 Jun 22;8(41):22917-22923. doi: 10.1039/c8ra02909a. eCollection 2018 Jun 21.
This paper describes a modified method to prepare monodisperse FeO magnetic nanoparticles with different shapes (cube, octahedron, and sphere). The shape of the magnetic nanoparticles could be conveniently controlled by changing the types of precursor/capping agent and concentration of capping agent. The prepared samples were characterized using scanning electron microscopy, X-ray diffraction and vibrating sample magnetometry. Cubes and octahedra were formed using ferrous sulfate heptahydrate as an iron source, ethylene glycol as a solvent and potassium hydroxide (KOH) as a capping agent while spheres were formed by using ferric chloride hexahydrate as an iron source, ethylene glycol as a solvent and ammonium acetate as a capping agent. By varying KOH concentration (0.5 M, 1 M, 1.5 M, and 5 M), the shape was transformed from cubes to octahedra because octahedra are developed dominantly at higher concentration of KOH within the reaction mixture. The magnetic studies show superparamagnetic behavior for all samples at room temperature. The FeO nanoparticles show the magnetic saturation values of 87 emu g, 85 emu g, and 82 emu g for spheres, cubes, and octahedrons, respectively.
本文描述了一种制备具有不同形状（立方体、八面体和球体）的单分散FeO磁性纳米颗粒的改进方法。通过改变前驱体/封端剂的类型和封端剂的浓度，可以方便地控制磁性纳米颗粒的形状。使用扫描电子显微镜、X射线衍射和振动样品磁强计对制备的样品进行了表征。以七水合硫酸亚铁为铁源、乙二醇为溶剂、氢氧化钾（KOH）为封端剂制备了立方体和八面体，而以六水合氯化铁为铁源、乙二醇为溶剂、乙酸铵为封端剂制备了球体。通过改变KOH浓度（0.5 M、1 M、1.5 M和5 M），形状从立方体转变为八面体，因为在反应混合物中较高浓度的KOH下八面体占主导地位。磁性研究表明，所有样品在室温下均表现出超顺磁性行为。FeO纳米颗粒的球体、立方体和八面体的磁饱和值分别为87 emu/g、85 emu/g和82 emu/g。
