Two-Step Poling for Improved Piezoelectric Properties in Lead-Free (Ba0.88Ca0.12)(Ti0.94Sn0.06)O3 Ceramic System

Pb-free (Ba0.88Ca0.12)(Ti0.94Sn0.06)O3 piezoelectric nanopowder was synthesized by solid-state reaction method. Piezoelectric properties were improved by two different approaches by optimizing poling conditions. Results indicate that poling near polymorphic phase boundary leads to the minimization of conduction current. However, low degree of poling observed indicates poor piezoelectricity. On the contrary, with Two-Step poling method, where the sample was sequentially subjected to low bias field at high temperature (step-1) and high bias field at low temperature (step-2), improved the piezoelectricity. Further, enhanced piezoelectric properties were obtained with optimized bias field of 1.25 kV/mm for step-1 with improved domain alignment.