Effect of A-site substitution on crystal component and dielectric properties in Bi0.5Na0.5TiO3 ceramics

A-site replacement is common used in optimizing the electric properties of Bi0.5Na0.5TiO3 (abbreviated to BNT). The effect of Ba2+ doping in BNT capacitor ceramics is investigated here. After the samples containing 6 at.% Ba2+ was sintered at 1180 deg C for 2 h, capacitor ceramics with enhanced dielectric properties was fabricated, compared with pure BNT ceramics. It can be concluded from the experiment results that Ba2+ replaced the ions in A-site, and the lattice structure was altered, which led to the improvement of dielectric properties in BNT ceramics. Then we discussed the phase transformation process from room temperature to 400 deg C according to the dielectric properties-temperature graphs.