Asx(i.e., the mole concentration of BT) increases, a tetragonal phase appears and increases continuously. Atx= 0.08, the ceramic becomes pure tetragonal phase.This suggests that a MPB of rhombohedral and tetragonal phases
resides betweenx= 0.065 andx= 0.07. This is evident by the splitting of the (20 2) diffraction peak to (00 2) and (20 0) peaks as observed in the (1x)BNT–xBT ceramic