Effect of domain switching contribution on polarization current, leakage current and switching charge density studied by PUND method in (Ba_(1-x), Ca_x)TiO_3 ceramics

摘要

The present study illustrates the effect of domain switching on polarization current and leakage current in (Ba1-xCax)TiO3 (0 = x = 0.4) lead-free ceramics prepared by sol-gel method. The influence of Ca2+ concentration on the structural, microstructure and dielectric properties of BaTiO3 (BT) was investigated. The study shows that domain switching has a significant effect on polarization current and switching leakage current behavior. Un-switching leakage current was observed to be lower than the switching leakage current in whole range of electric field due to restrict the space charges contribution in the absent of domain switching effect. The highest polarization current and lowest leakage current were achieved in the composition x = 0.2. Effect of frequency into polarization current has been introduced, where the current peak increased and shifted to higher electric field by increasing the applied frequency due to the high rate change of electric field corresponding domain switching rate. The difference between remnant polarization estimated by P-E loop and Positive Up Negative Down (PUND) methods has been highlighted. The results show that the remnant polarization appraised by PUND method is lower than the value estimated by P-E loop due to absence of the leakage current contribution.