New lead-free piezoelectric ceramics 0.96[{Bi0.5 (Na0.84 K0.16)0.5}1-xLax(Ti1-y Nby)O3]-0.04SrTiO3 (BNKT-ST-LN, where x = y = 0.00 ≤ (x = y) ≤ 0.015) were synthesized using the conventional solid-state reaction method. Their crystal structure, microstructure, and electrical properties were investigated as a function of the La and Nb (LN) content. The X-ray diffraction patterns revealed the formation of a single-phase perovskite structure for all the LN-modified BNKT-ST ceramics in this study. The temperature dependence of the dielectric curves showed that the maximum dielectric constant temperature (Tm) shifted towards lower temperatures and the curves became more diffuse with an increasing LN content. At the optimum composition (LN 0.005), a maximum value of remnant polarization (33 C/cm2) with a relatively low coercive field (22 kV/cm) and high piezoelectric constant (215 pC/N) was observed. These results indicate that the LN co-modified BNKT-ST ceramic system is a promising candidate for lead-free piezoelectric materials.

• Rizwan Ahmed Malik(School of Advanced Material Engineering, Changwon National University)
• Ali Hussain(School of Advanced Material Engineering, Changwon National University)
• Adnan Maqbool(School of Advanced Material Engineering, Changwon National University)
• Arif Zaman(Department of Physics, Abdul Wali Khan University, Mardan, KPK, Pakistan)
• Tae Kwon Song(School of Advanced Material Engineering, Changwon National University)
• Won Jeong Kim(Department of Physics, Changwon National University)
• Myong Ho Kim(School of Advanced Material Engineering, Changwon National University) Corresponding author