Influence of niobium doping on the electrical properties of 0.58Pb(Sc1/2Nb1/2)O3-0.42PbTiO3 single crystal

Piezoelectric single crystals of 0.58Pb(Sc1/2Nb1/2)-0.42PbTiO3 and Nb5+-doped PSN-PT have been grown using flux technique. It is believed that the addition of Nb5+ creates lead vacancy (VPb) in order to compensate charge neutrality. The structural distortion that occured in the doped crystals has been revealed through broadening of some peaks in X-ray diffraction studies. Niobium content that increased from 0.50 to 1.00 mol% might have induced more defect dipoles associated with Vpb. This plays a significant role in improving the ferroelectric, dielectric and piezoelectric properties. Our observations clearly show an increase in the spontaneous polarization (Pr), dielectric constant at room temperature, degree of diffuseness and transition temperature (Tc) and also a decrease in coercive field. The reasons behind these enhanced electrical properties are discussed in detail.