Ferroelectric and piezoelectric properties of (Ba0.7Ca0.3)(Ti1−xSnx)O3 lead-free ceramics

The ferroelectric and piezoelectric properties of Sn⁴⁺ modified (Ba_0.7Ca_0.3)(Ti_1-xSn_x)O₃, (with x = 0.000 to 0.100 in steps of 0.025) lead free electroceramics were investigated. With Sn⁴⁺ substitution, a structural phase transition from pure tetragonal to pseudo-cubic structure has been observed; which strongly influence the ferroelectric/ piezoelectric nature of the samples. At room temperature, all the samples exhibit typical polarization-electric field hysteresis as well as field induced strain butterfly loop which confirms the ferroelectric and piezoelectric nature. As Sn⁴⁺ content increases, the ferroelectric properties seems to be suppressed while the piezoelectric properties gets improved up to x = 0.075 and then decreased. Moderately high remanent polarization (P_r) and low coercive field (E_c) were observed for all compositions, which may be essential for storage and switching applications.