The Study of Magnetic Properties for Non-Magnetic Ions Doped BiFeO3

Yongtao Li; Liqing Liu; Dehao Wang; Hongguang Zhang; Xuemin He; Qi Li

doi:10.3390/ma14154061

The Study of Magnetic Properties for Non-Magnetic Ions Doped BiFeO₃

Materials (Basel). 2021 Jul 21;14(15):4061. doi: 10.3390/ma14154061.

Authors

Yongtao Li^{1

2

3}, Liqing Liu^{1

3}, Dehao Wang², Hongguang Zhang^{1

3}, Xuemin He^{1

3}, Qi Li⁴

Affiliations

¹ School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
² College of Electronic Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
³ New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing 210023, China.
⁴ School of Physics, Southeast University, Nanjing 211189, China.

Abstract

BiFeO₃ is considered as a single phase multiferroic. However, its magnetism is very weak. We study the magnetic properties of BiFeO₃ by Cu and (Cu, Zn). Polycrystalline samples Bi(Fe_0.95Cu_0.05)O₃ and BiFe_0.95(Zn_0.025Cu_0.025)O₃ are prepared by the sol-gel method. The magnetic properties of BiFe_0.95(Zn_0.025Cu_0.025)O₃ are greater than that of BiFeO₃ and Bi(Fe_0.95Cu_0.05)O₃. The analyses of X-ray absorption fine structure data show that the doped Cu atoms well occupy the sites of the Fe atoms. X-ray absorption near edge spectra data confirm that the valence state of Fe ions does not change. Cu and Zn metal ion co-doping has no impact on the local structure of the Fe and Bi atoms. The modification of magnetism by doping Zn can be understood by the view of the occupation site of non-magnetically active Zn²⁺.

Keywords: XAFS; local structure; magnetic properties; sol-gel method.