The Effects of Nickel Substitution on Bismuth Ferrite

In this paper, we studied the electrical conduction and spectroscopic properties of the Ni-doped BiFeO3 (BFO), which were prepared by the sol–gel method and sintered into powders or compact pellets. The changes of sintering conditions due to the addition of Ni were studied and the solubility of Ni in BFO was estimated. Photoluminescence measurements were carried out for the Ni-doped BFO samples and observed four emissions at about 451, 468, 513, and 689 nm, respectively. The resistivity of the Ni doped BFO was reduced by more than three orders of magnitude than the un-doped BFO. The conductivity vs. temperature measurements revealed three activation energies, whose levels in the band gap matched well with the observed PL emission wavelengths.