Aguirre-Espinosa Julio C, Sánchez-De Jesús Félix, Cortés-Escobedo Claudia A, Bolarín-Miró Ana M
Área Académica de Ciencias de la Tierra y Materiales, Universidad Autónoma del Estado de Hidalgo, Mineral de la Reforma, Hidalgo 42184, Mexico.
Centro de Investigación e Innovación Tecnológica, Instituto Politécnico Nacional, Ciudad de México 02250, Mexico.
Materials (Basel). 2025 Jun 25;18(13):3014. doi: 10.3390/ma18133014.
The effect of strontium substitution on the crystal tructure, as well as the magnetic, and electrical properties of lanthanum ferrite (LaFeO) synthesized by high-energy ball milling, is studied, with an emphasis on magnetodielectric coupling. X-ray diffraction (XRD) confirmed the successful synthesis of orthorhombic LaSrFeO for doping levels up to 0.2 mol. At 0.3 mol Sr, two phases appear: LaSrFeO and LaSrFeO, the latter being metastable. This phase vanishes at 0.5 mol. The Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (SEM-EDS) analysis confirmed these results using a vibrating sample magnetometer (VSM), whose measurements show ferromagnetism at 0.1 and 0.3 mol Sr, attributed to crystal distortion, magnetic spin rearrangement, and as consequence, modifications in the double-exchange interactions. Dielectric tests reveal that higher Sr concentrations lead to increased relative permittivity, dielectric losses, and conductivity, linked to oxygen vacancy formation. This study demonstrates a room-temperature magnetodielectric coupling of 32% in Sr-doped lanthanum ferrite, highlighting its potential for technological applications.
研究了锶取代对通过高能球磨合成的镧铁氧体（LaFeO）的晶体结构以及磁性能和电性能的影响，重点关注磁电耦合。X射线衍射（XRD）证实了对于高达0.2摩尔的掺杂水平成功合成了正交晶系的LaSrFeO。在0.3摩尔锶时，出现两相：LaSrFeO和LaSrFeO，后者是亚稳相。该相在0.5摩尔时消失。傅里叶变换红外光谱（FT-IR）以及扫描电子显微镜与能量色散X射线光谱（SEM-EDS）分析使用振动样品磁强计（VSM）证实了这些结果，其测量显示在0.1和0.3摩尔锶时存在铁磁性，这归因于晶体畸变、磁自旋重排以及因此导致的双交换相互作用的改变。介电测试表明，较高的锶浓度会导致相对介电常数、介电损耗和电导率增加，这与氧空位的形成有关。这项研究表明，在掺锶镧铁氧体中室温磁电耦合为32%，突出了其在技术应用方面的潜力。
