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 ( V Pb ) 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 V pb . This plays a significant role in improving the ferroelectric, dielectric and piezoelectric properties. Our observations clearly show an increase in the spontaneous polarization ( P r ) , dielectric constant at room temperature, degree of diffuseness and transition temperature ( T c ) and also a decrease in coercive field. The reasons behind these enhanced electrical properties are discussed in detail.