Microstructural and magnetic analysis of Sr-doped CoFe2O4 spinels by Rietveld refinement

IF 4.2 4区材料科学 Q2 MATERIALS SCIENCE, CERAMICS

Journal of Sol-Gel Science and Technology Pub Date : 2026-04-30 DOI:10.1007/s10971-026-07169-1

Amel Mohamed Abouelnaga, Amany M. El Nahrawy

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引用次数: 0

Abstract

Nanoparticles of cobalt ferrite (CoFe₂O₄) and strontium-doped cobalt ferrite (Co₁₋ₓSrₓFe₂O₄, where x = 0.0–0.4) were produced using a diethylamine-assisted sol-gel method, followed by calcination at 600 °C. The microstructural properties were studied through Rietveld refinement of X-ray diffraction (XRD) data, which revealed the presence of a cubic spinel phase, alongside secondary Sr-containing phases at higher doping levels. The crystallite size decreased from 41 nm (for x = 0.0) to 34 nm (for x = 0.4), indicating grain refinement due to lattice strain and limited solubility of Sr. Scanning electron microscopy (SEM) analysis revealed a homogeneous formation of nanoparticles, while Fourier-transform infrared spectroscopy (FTIR) confirmed that the spinel structure was maintained, with band shifts caused by the dopant. Magnetic studies demonstrated a significant decrease in saturation magnetization as the Sr content increased, reaching 30.27 emu/g at x = 0.4. This reduction is ascribed to the weakening of the effect of magnetic ions and the formation of non-magnetic secondary phases. Coercivity peaked at x = 0.2, indicating an optimal enhancement of magnetic anisotropy. These findings confirm the impact of Sr²⁺ doping on both microstructural and magnetic properties, signifying promising applications in spintronics, magnetic storage, and various functional ferrite-based materials.

Graphical Abstract

The alternative text for this image may have been generated using AI.

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锶掺杂CoFe2O4尖晶石的Rietveld细化显微组织和磁性分析

采用二乙胺辅助溶胶-凝胶法制备了铁酸钴纳米颗粒（CoFe₂O₄）和掺杂锶的铁酸钴（Co₁ₓSrₓFe₂O₄，其中x = 0.0-0.4），然后在600℃下煅烧。通过x射线衍射（XRD）数据的Rietveld细化研究了微观结构性能，发现存在立方尖晶石相，以及高掺杂水平的次生含sr相。晶体尺寸从41 nm （x = 0.0）减小到34 nm (x = 0.4)，表明由于晶格应变和sr的有限溶解度导致晶粒细化。扫描电镜（SEM）分析显示纳米颗粒形成均匀，而傅里叶变换红外光谱（FTIR）证实尖晶石结构保持不变，但掺杂引起了条带移位。磁性研究表明，随着Sr含量的增加，饱和磁化强度显著降低，在x = 0.4时达到30.27 emu/g。这种减少是由于磁性离子的作用减弱和非磁性二次相的形成。矫顽力在x = 0.2处达到峰值，表明磁各向异性得到了最佳增强。这些发现证实了Sr 2 +掺杂对微观结构和磁性能的影响，这意味着在自旋电子学、磁存储和各种功能铁氧体基材料中有很好的应用前景。此图像的替代文本可能是使用AI生成的。

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来源期刊

Journal of Sol-Gel Science and Technology 工程技术-材料科学：硅酸盐

CiteScore

4.70

自引率

4.00%

发文量

280

审稿时长

2.1 months

期刊介绍： The primary objective of the Journal of Sol-Gel Science and Technology (JSST), the official journal of the International Sol-Gel Society, is to provide an international forum for the dissemination of scientific, technological, and general knowledge about materials processed by chemical nanotechnologies known as the "sol-gel" process. The materials of interest include gels, gel-derived glasses, ceramics in form of nano- and micro-powders, bulk, fibres, thin films and coatings as well as more recent materials such as hybrid organic-inorganic materials and composites. Such materials exhibit a wide range of optical, electronic, magnetic, chemical, environmental, and biomedical properties and functionalities. Methods for producing sol-gel-derived materials and the industrial uses of these materials are also of great interest.