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

Ti4+ substituted (Bi0.9Ba0.1)(Fe1−yTiy)O3 ceramics (0.0 ≤ y ≤ 0.15) were synthesized by auto combustion method. Rietveld refinement reveals a transformation from rhombohedral to tetragonal with the Ti4+ doping content at y = 0.05. Effect of Ti4+ doping on the dielectric properties of Ba2+ doped BiFeO3 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 Ti4+ content and then after decreases with further increase in Ti4+ concentration. The electrical conductivity of Bi0.9Ba0.1Fe1−yTiyO3 ceramics obeys the Arrhenius law, revealing the controlled conduction mechanism of oxygen vacancies at the higher range of temperature. The highest d33 value of 15.8 pC/N was exhibited by the composition with Ti4+ doping at y = 0.05. Ti4+ doped BBFO ceramics showed similar behavior of weak ferromagnetism as Bi0.9Ba0.1FeO3. Also, magnetization was found to increase with Ti4+ doping content up to 0.05 and then decreases with further increase in doping concentration.