The Study of Magnetic Properties for Non-Magnetic Ions Doped BiFeO(3)

BiFeO(3) is considered as a single phase multiferroic. However, its magnetism is very weak. We study the magnetic properties of BiFeO(3) by Cu and (Cu, Zn). Polycrystalline samples Bi(Fe(0.95)Cu(0.05))O(3) and BiFe(0.95)(Zn(0.025)Cu(0.025))O(3) are prepared by the sol-gel method. The magnetic properties of BiFe(0.95)(Zn(0.025)Cu(0.025))O(3) are greater than that of BiFeO(3) and Bi(Fe(0.95)Cu(0.05))O(3). 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 Zn(2+).