The Cation Distributions of Zn-doped Normal Spinel MgFe2O4 Ferrite and Its Magnetic Properties

Materials

Junwei Zhang¹  Yong Peng¹  Lei Gao¹  Zhipeng Hou²  Jiaqi Ju³  Xue Zeng³ 

[1] Electron Microscopy Centre of Lanzhou University and Key Laboratory of Magnetism and Magnetic Materials of the Ministry of Education, School of Materials and Energy, Lanzhou University, Lanzhou 730000, China;Guangdong Provincial Key Laboratory of Optical Information Material and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China;School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070, China;

关键词: ferrites;    nanofibers;    C_S-STEM characterization;    atomic structure;    magnetic properties;   

DOI  :  10.3390/ma15072422

来源: DOAJ

【 摘 要 】

Determining the exact occupation sites of the doping ions in spinel ferrites is vital for tailoring and improving their magnetic properties. In this study, the distribution and occupation sites of cations in MgFe₂O₄ and Zn-doped MgFe₂O₄ ferrite are imaged by Cs-STEM. The experimental STEM images along [001], [011] and [111] orientations suggest that the divalent Mg²⁺ cations occupy all A sites, and the trivalent Fe³⁺ cations occupy all B sites in MgFe₂O₄ ferrite prepared by electrospinning, which is consistent with the normal spinel structure. We further clarify that the preferred sites of dopant Zn²⁺ ions are Fe³⁺ crystallographic sites in the Zn-doped MgFe₂O₄ ferrite nanofibers. Magnetic measurements show that Zn doping affects the spin states of the Fe³⁺, and the Fe³⁺-O²⁻-Fe³⁺ super-exchange interaction leads to enhancements in the magnetization and reduction in the Curie temperature. Our work should contribute a significant step toward eventually realizing the practical application of doped spinel ferrites.

【 授权许可】

Unknown