Effect of Porosity on Functional Properties of Lead-Free Piezoelectric BaZrTiO Porous Ceramics

The present paper reports the dependence of dielectric, ferroelectric and piezoelectric properties on the porosity level in BaZrTiO ceramics with porosity from 5% to 21%. Microporosity with 0-3 connectivity has been produced using PMMA microspheres as a sacrificial template. The functional properties (dielectric, ferroelectric and piezoelectric effect) are mostly affected by the "dilution effect": permittivity decreases by 40% when porosity increases by 21%, and P decreases from 13 to 5 µC/cm while the P is in the range of (2-8) µC/cm. However, the reduction of the zero-field permittivity and hysteretic behaviour of ε(E) while the tunability level is still high makes from porous ceramics interesting materials for tunability application.