Pinto García Cristóbal, Maine Arianne, Valenzuela-Fernández Rodrigo A, Aliaga Cerón Álvaro, Barahona Huenchumil Patricia, Peña Octavio, Álvarez-Serrano Inmaculada, Ibáñez Andrés, Melo Francisco, Galdámez Silva Antonio
Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile.
SMAT-C, Departamento de Física, Universidad de Santiago de Chile, Av. Víctor Jara 3493, Estación Central, Santiago 9160000, Chile.
Nanomaterials (Basel). 2024 Jun 3;14(11):971. doi: 10.3390/nano14110971.
A new series of [FeLn]O nanoparticles, with Ln = Gd; Dy; Lu and = 0.05; 0.1; 0.15, was synthesized using the coprecipitation method. Analyses by X-ray diffraction (XRD), Rietveld refinement, and high-resolution transmission electron microscopy (HRTEM) indicate that all phases crystallized in space group Fd3¯m, characteristic of spinels. The XRD patterns, HRTEM, scanning electron microscopy analysis (SEM-EDS), and Raman spectra showed single phases. Transmission electron microscopy (TEM), Rietveld analysis, and Scherrer's calculations confirm that these materials are nanoparticles with sizes in the range of ~6 nm to ~13 nm. Magnetic measurements reveal that the saturation magnetization (Ms) of the as-prepared ferrites increases with lanthanide chemical substitution (), while the coercivity (Hc) has low values. The Raman analysis confirms that the compounds are ferrites and the Ms behavior can be explained by the relationship between the areas of the signals. The magnetic measurements indicate superparamagnetic behavior. The blocking temperatures (T) were estimated from ZFC-FC measurements, and the use of the Néel equation enabled the magnetic anisotropy to be estimated.
采用共沉淀法合成了一系列新的[FeLn]O纳米颗粒，其中Ln = Gd、Dy、Lu， = 0.05、0.1、0.15。通过X射线衍射（XRD）、Rietveld精修和高分辨率透射电子显微镜（HRTEM）分析表明，所有相均在空间群Fd3¯m中结晶，这是尖晶石的特征。XRD图谱、HRTEM、扫描电子显微镜分析（SEM-EDS）和拉曼光谱均显示为单相。透射电子显微镜（TEM）、Rietveld分析和Scherrer计算证实，这些材料是尺寸在约6纳米至约13纳米范围内的纳米颗粒。磁性测量表明，所制备铁氧体的饱和磁化强度（Ms）随着镧系元素化学取代量（）的增加而增大，而矫顽力（Hc）值较低。拉曼分析证实这些化合物是铁氧体，Ms行为可以通过信号面积之间的关系来解释。磁性测量表明存在超顺磁行为。通过零场冷却-场冷却（ZFC-FC）测量估计了阻塞温度（T），并使用奈尔方程估计了磁各向异性。
