Fluorine doping effects on the magnetic and electric properties of BiFeO3

Electron-doping introduced fluorine (F) replacement of the oxygen in BiFeO3 (BFO) can be compensated by the valence change of iron from Fe3+ to Fe2+. We successfully incorporate F in BFO by sol–gel method. F-doping is found to significantly enhance the ferromagnetism up to nearly two order for x = 0.25 compared with x = 0. This study provides direct evidence that the multiferroic characteristics of BiFeO3 are sensitive to the anion doping, such as F, providing a convenient alternative to manipulate the magnetization and electric polarization in multiferroic oxides.