Oxygen-vacancy-related conduct behavior and ferromagnetism of 0.7BaTiO3-0.3BaFe12O19 multiferroic composites

Abstract The structural, morphological, conductive and magnetic properties of 0.7BaTiO 3 -0.3BaFe 12 O 19 (BT-BFO) ceramics were investigated as a function of oxygen vacancies by post-annealing in N 2 and O 2 . Raman spectra shown that the samples had no other impurity phases, the structure of BaTiO 3 changed from tetragonal to hexagonal after annealing in N 2 . The conduction activation energy about 0.3 eV indicated that single-charged oxygen vacancies ( V O • ) make contribution to the conduction process. A simple model describing the conduction process was proposed to explain the role of oxygen vacancies in the conduction mechanism of BT-BFO ceramics. V O • played a crucial role in mediating ferromagnetism in BT-BFO ceramics, ceramics annealed in N 2 shows a 16% increase in magnetization.