Double hysteresis loop in BaTi1-xHfxO3 ferroelectric ceramics

Hafnium doped barium titanate ceramics were prepared by the conventional solid-state reaction method. The structural, microstructure and ferroelectric properties were analyzed with varying Hf concentration. It is found that the crystal structure of the solid solution remains in tetragonal phase with the decrease of tetragonality by increasing of Hf ion concentration. The grain growth habit is significantly depending upon Hf ion concentration. The remnant polarization and coercive field is decreased along with narrowing of the central portion of the ferroelectric hysteresis loop with the increasing of Hf ion concentration. The double hysteresis loops are associated with the onset of an antiferroelectric order and it is increased with increasing of Hf ion concentration.