Pyroelectricity in calcium substituted sodium bismuth titanate layer structured ferroelectric ceramics

Pyroelectric properties of bismuth layer structured calcium substituted sodium bismuth titanate (Na_0·5Bi_0·5)_1−x Ca _x Bi₄Ti₄O₁₅ withx=0 (NBT) andx=0·1 (0·1 NCBT) were studied by measuring the current under short circuit condition. Spontaneous polarization and figures of merit were evaluated from the measured values of pyroelectric coefficients, dielectric constant and loss tangent. The pyroelectric properties were studied in poled and short circuit condition from 30°C to 700°C. The results obtained were discussed in the light of dielectric and conductivity properties of the samples.