Structural distortion and phase transition studies of Aurivillius type Sr1−xPbxBi2Nb2O9 ferroelectric ceramics

In this paper, effects of lead doping on the lattice response and phase transitions of Sr1−xPbxBi2Nb2O9 (x=0.0-0.5 in steps of 0.1) ferroelectric ceramics are reported. It is observed that structure attains more tetragonality with doping of lead up to 40%. Increased orthorhombic distortion is observed for undoped SBN and 50 at.% lead substituted SBN. Phase transitions for all samples were studied using Curie temperature measurements and are explained in terms of lattice response of these ceramics. Sample with x=0.5 shows decreased tetragonal strain and Curie temperature. Relationship of polarization with lattice response is discussed.