The Effect of Ca or Ba Substitution on the Properties in Bi0.87La0.05B0.08FeO3 (B＝Ca, Ba) Ceramics

Multiferroic Bi0.87La0.05B0.08FeO3 (B＝Ca2＋, Ba2＋) ceramics were prepared by sol-gel method and spark plasma sintering with the protection of CeO2 powders. The substitution of Ba increases the samples’ magnetic properties, which leads to higher leakage current and makes the bulk ceramics high dielectric loss (0.1-0.2). In contrast, Bi0.87La0.05Ca0.08FeO3 ceramics have high breakdown field strength (220 kV/cm) and low loss (tand~2%), and the dielectric constant is stable (about 100) in the frequency between 102 and 106 Hz. Meanwhile, Ca doping improves the ceramic coercive field and ferroelectric domains do not switch under 220 kV/cm, leading to slim ferroelectric loops.