Effects of Mg substitution on the structural and magnetic properties of Coo.sNi0.5xMgxFe2O4 nanoparticle ferrites

• Published in: 中国物理B：英文版 2016 (4), p.358-364
• Main Author: R M Rosnan Z Othaman R Hussin Ali A Ati Alireza Samavati Shadab Dabagh samad Zare
• Format: Article
• Language: English
• Subjects: X射线衍射分析; 场发射扫描电子显微镜; 尖晶石结构; 尖晶石铁氧体; 振动样品磁强计; 磁性能; 纳米晶; 镁掺杂
• ISSN: 1674-1056; 2058-3834

In this study, nanocrystalline Co-Ni-Mg ferrite powders with composition Coo.5Nio.5-xMgxFe2O4 are successfully synthesized by the co-precipitation method. A systematic investigation on the structural, morphological and magnetic properties of un-doped and Mg-doped Co-Ni ferrite nanoparticles is carried out. The prepared samples are characterized using x-ray diffraction （XRD） analysis, Fourier transform infrared spectroscopy （FTIR）, field emission scanning electron microscopy （FESEM）, and vibrating sample magnetometry （VSM）. The XRD analyses of the synthesized samples confirm the formation of single-phase cubic spinel structures with crystallite sizes in a range of - 32 nm to - 36 nm. The lat- tice constant increases with increasing Mg content. FESEM images show that the synthesized samples are homogeneous with a uniformly distributed grain. The results of IR spectroscopy analysis indicate the formation of functional groups of spinel ferrite in the co-precipitation process. By increasing Mg2- substitution, room temperature magnetic measurement shows that maximum magnetization and coercivity increase from - 57.35 emu/g to - 61.49 emu/g and - 603.26 Oe to 684.11 Oe （l Oe = 79.5775 A.m-l）, respectively. The higher values of magnetization Ms and Mr suggest that the opti- mum composition is Co0.5Ni0.4Mg0.1Fe204 that can be applied to high-density recording media and microwave devices.