真空和空气冷凝CoFe2O4纳米粒子的结构和磁性特性
Balaji Srikanth Ragunath1, A Thileeba1, K R S Preethi Meher2
1Advanced Nanostructured Materials Laboratory, Department of Physics, School of Electrical & Electronics Engineering, SASTRA Deemed to be University, Thirumalaisamudram, Thanjavur 613401, Tamil Nadu, India.
Solid state communications
|December 3, 2025
概括
合成并化了铁 (CoFe2O4) 纳米粒子. 与空气回火不同的是,真空回火通过促进离子迁移和氧气空缺来增强磁性,而空气回火则提高了磁性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 固态化学 固态化学
背景情况:
- 铁 (CoFe2O4) 纳米粒子 (NP) 是重要的磁性材料.
- 了解化大气对CFO NP属性的影响对于优化其应用至关重要.
研究的目的:
- 调查化大气 (空气与真空) 对CoFe2O4NP的结构性,微结构性和磁性特性的影响.
- 阐明对属性变化负责的机制,特别是增强磁化.
主要方法:
- 对于CFO NP合成的共同降水技术.
- 在空气和真空大气下,在高达1273K的温度下火.
- 用于结构分析的X射线衍射 (XRD).
- 传输电子显微镜 (TEM) 用于微观结构的表征.
- 拉曼光谱检测用于确认离子迁移.
主要成果:
- 所有样品的脊柱结构通过XRD确认.
- 通过TEM观察到的26 ± 7nm的平均原始CFONP大小.
- 与空气 (20.4 kJ/mol) 相比,真空制样品的激活能量 (14.5 kJ/mol) 较低.
- 在真空化下显著提高了和磁化 (80emu/g) 与空气化 (76emu/g) 相比.
结论:
- 真空回火促进了旋转结构内的离子迁移,从而改善了磁性特性.
- 电离迁移和氧气空缺的产生是增强和磁化在真空化CFO NP中的关键因素.
- 这些发现提供了通过受控回火过程来定制磁性纳米材料的见解.
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