Abstract Iron oxide nanoparticles (NPs) were prepared using a polyol method from Fe(III) acetylacetonate in the presence of polyvinylpyrrolidone (PVP). These particles were subsequently calcined and annealed using a digitally controlled furnace from 200 to 1000 C producing crystallization. The morphology of the untreated nanoclusters and each calcined NP sample were observed under a scanning electron microscope (SEM) coupled with energy-dispersive X-ray (EDX) and their correlation explored. The SEM confirmed that the spherical NPs produced by the polyol method maintained their morphology during calcination at different temperatures. The extent of agglomeration was analyzed using dynamic light spectroscopy (DLS), which were measured as 1.0 μm. The effect of calcination on structural changes was monitored by X-ray diffraction (XRD), this revealed the presence of both hematite (α-Fe2O3) and maghemite (γ-Fe2O3) phases at low temperatures and the complete transformation into hematite at higher temperature. UV–Visible and fluorescent spectroscopy were used to analyze the optical properties and vibratory sample magnetometer (VSM) confirmed its paramagnetic characters.

中文翻译：

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多元醇和煅烧法分级合成氧化铁纳米颗粒及其光学和磁性行为的测定

摘要 在聚乙烯吡咯烷酮 (PVP) 存在下，使用多元醇法从乙酰丙酮 Fe(III) 制备氧化铁纳米粒子 (NPs)。这些颗粒随后使用数控炉从 200 到 1000 摄氏度进行煅烧和退火，产生结晶。在扫描电子显微镜 (SEM) 和能量色散 X 射线 (EDX) 耦合下观察未处理纳米团簇和每个煅烧 NP 样品的形态，并探讨了它们的相关性。SEM 证实多元醇法生产的球形纳米颗粒在不同温度下煅烧过程中保持其形态。使用动态光光谱 (DLS) 分析团聚程度，测量结果为 1.0 μm。通过 X 射线衍射 (XRD) 监测煅烧对结构变化的影响，这揭示了赤铁矿 (α-Fe2O3) 和磁赤铁矿 (γ-Fe2O3) 相在低温下的存在，并在高温下完全转变为赤铁矿。紫外-可见光和荧光光谱用于分析光学特性，振动样品磁强计（VSM）证实了其顺磁特性。