New quaternary BNT-BT-PMN-PT ceramic: ferro-/piezo-/pyroelectric characterizations

A near morphotropic phase boundary composition of a new quaternary ceramic 0.47(Bi0.5Na0.5)TiO3-0.04BaTiO(3)-0.31Pb(Mg1/3Nb2/3)O-3-0.18PbTiO(3) [BNT-BT-PMN-PT] has been synthesized using the solid state reaction method. The ceramics were characterized for their ferroelectric properties along with dielectric and piezoelectric characteristics. High value of maximum dielectric permittivity (similar to 4140) and transition temperature (T-c similar to 190 degrees C) with low dielectric loss (<0.5) were displayed. Well-shaped saturated PE hysteresis loop with high value of remanent polarization (P-r=13.09 mu C/cm(2)) and coercive field (E-c=16.56kV/cm) with excellent fatigue resistance (over 10(7) cycles) were observed. Together with the conventional P-E hysteresis used for recording the P-r value, which contains false contributions from various polarization artifacts, true remanent hysteresis task was used to unveil the practically usable polarization which was found to be similar to 93% that of the P-r value obtained using conventional hysteresis, suggesting high ferroelectric quality of the quaternary ceramic system. Time-dependent compensated' ferroelectric loops were traced to analyze the resistive-leakage nature of BNT-BT-PMN-PT system which showed that the system does not show degradation of ferroelectric properties due to change in frequency of applied field. This validates the potential of the material in devices such as actuators where fields are switched at different rates. The ceramic displayed good pyroelectric character in temperature range 95-110 degrees C. Further, the butterfly loop revealed the piezoelectric coefficient d(33)(*) value to be 177pm/V. Overall, high T-c, high ferroelectric quality, stability under cyclic electric field and high d(33) show that BNT-BT-PMN-PT (with lesser toxicity) is an attractive ceramic for consumer electronic device applications.