Abstract α-Fe2O3 nanoparticles were synthesized via co-precipitation technique using ferric and ferrous salts and potassium hydroxide as precipitation agents. The samples were calcined at 350 °C, 550 °C and 750 °C for 3 hours. The obtained iron oxide was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and dynamic light scattering (DLS). Crystallinity of the sample was studied by X-ray diffraction. SEM micrographs showed nonuniform size distribution of the particles forming agglomerates. TGA analysis revealed trace amount of weight loss and material stability for the samples calcined at temperatures above 500 °C. DLS results indicated that increasing of annealing temperature resulted in reduction of the particle size and more uniform size distribution. At the maximum annealing temperature of 750 °C, the mean diameter of the particles of 100 nm was observed.

中文翻译：

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α-Fe2O3纳米粒子的合成及退火温度对其性能的影响分析

摘要 以铁盐、亚铁盐和氢氧化钾为沉淀剂，通过共沉淀技术合成了α-Fe2O3纳米颗粒。样品在 350°C、550°C 和 750°C 下煅烧 3 小时。通过X射线衍射（XRD）、热重分析（TGA）、扫描电子显微镜（SEM）和动态光散射（DLS）对所得氧化铁进行表征。通过X射线衍射研究样品的结晶度。SEM显微照片显示形成附聚物的颗粒的尺寸分布不均匀。TGA 分析表明，在高于 500 °C 的温度下煅烧的样品有痕量的重量损失和材料稳定性。DLS 结果表明，提高退火温度导致粒度减小和粒度分布更均匀。