Magnetite nanoparticles (Fe₃O₄) were prepared by chemical coprecipitation method using ferric chloride (FeCl₃) and heptahydrate ferrous sulfate (FeSO₄·7H₂O) salts employing sodium hydroxide (NaOH) as a precipitant. To determine the size, shape, and chemical makeup of the produced magnetite nanoparticles, the generated powders were examined by transmission electron microscope, scanning electron microscope, atomic force microscope, and X-ray diffractometer. It was found that the magnetite powder had made a face-centered cubic crystal structure and spherical-like particle form with particle diameters of about 30 nm. The magnetic properties of magnetite nanoparticles were evaluated using a vibrating sample magnetometer. The obtained superparamagnetic properties of the produced nanoparticles, with saturation magnetization and coercivity of 50.75 emu/g and 30.09 Oe, respectively, allow them for applications in drug delivery, MRI contrast agent, catalysis, degradation of antibiotics, antibacterial activity, removal of heavy metals and organic dyes, etc.

中文翻译：

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化学共沉淀法合成并在 250°C 下煅烧 4 小时的超顺磁性磁铁矿纳米颗粒 (Fe3O4) 的晶体学、形态、磁性和热学表征

以氯化铁(FeCl ₃ )和七水硫酸亚铁(FeSO ₄ ·7H ₂ O)盐为沉淀剂，氢氧化钠(NaOH)为沉淀剂，采用化学共沉淀法制备了磁铁矿纳米颗粒₍ Fe 3 O _{4 )。}为了确定所生产的磁铁矿纳米颗粒的尺寸、形状和化学组成，通过透射电子显微镜、扫描电子显微镜、原子力显微镜和 X 射线衍射仪对生成的粉末进行了检查。发现磁铁矿粉末具有面心立方晶体结构和球形颗粒形式，粒径约为30 nm。使用振动样品磁力计评估磁铁矿纳米粒子的磁性。所生产的纳米颗粒具有超顺磁特性，饱和磁化强度和矫顽力分别为50.75 emu/g和30.09 Oe，使其可用于药物输送、MRI造影剂、催化、抗生素降解、抗菌活性、重金属去除等领域以及有机染料等。