Structural Phase Diagram of BZT-BCT

200 pC/N) and electromechanical coupling factor k for BZT-xBCT for varying X values (32BCT and 50BCT). The dielectric peaks observed at Tc = 376 and 303 K corresponding to C-T and T-R phase transitions, respectively, further are in correlation with the phase transition observed from XRD. These frequency-independent anomalies in real (ej.) and imaginary (ej) parts of dielectric permittivity show non-relaxor behavior of these samples. 

It is important to investigate the origin of the colossal piezoelectric and dielectric properties observed in the BZT-xBCT solid solution [18]. It has been proposed that along phase boundaries an extreme reduction or disappearance of the polarization anisotropy leads to a low barrier between (001) 

T and (111) R polarization states. This establishes instability of the polarization vector against rotation, thus facilitating an easy polarization rotation. 

In addition to BZT-xBCT, the other system that has been studied extensively by the researchers for both fundamental understanding and applications is sodiimi bismuth titanate, Nao.5Bio.5Ti03 (NBT). NBT and its solid solutions have been extensively studied because of their exceptionally high electrostrain [20,21]. In addition, NBT coidd be a potential candidate in the search for lead-free piezoelectric materials. From the structural aspects, NBT is 

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