Investigation on the effect of Ti doping on dielectric, impedance and magnetic properties of Ba2+-substituted BiFeO3 ceramics

Ti 4+ substituted (Bi 0.9 Ba 0.1 )(Fe 1−y Ti y )O 3 ceramics (0.0 ≤ y ≤ 0.15) were synthesized by auto combustion method. Rietveld refinement reveals a transformation from rhombohedral to tetragonal with the Ti 4+ doping content at y = 0.05. Effect of Ti 4+ doping on the dielectric properties of Ba 2+ doped BiFeO 3 was studied from room temperature to 400 °C in wide range of frequency. Initially, the dielectric loss was found to increase in ceramics with low Ti 4+ content and then after decreases with further increase in Ti 4+ concentration. The electrical conductivity of Bi 0.9 Ba 0.1 Fe 1−y Ti y O 3 ceramics obeys the Arrhenius law, revealing the controlled conduction mechanism of oxygen vacancies at the higher range of temperature. The highest d 33 value of 15.8 pC/N was exhibited by the composition with Ti 4+ doping at y = 0.05. Ti 4+ doped BBFO ceramics showed similar behavior of weak ferromagnetism as Bi 0.9 Ba 0.1 FeO 3 . Also, magnetization was found to increase with Ti 4+ doping content up to 0.05 and then decreases with further increase in doping concentration.