Enhanced piezoelectric properties of (Bi0.5Na0.5)1－xBax TiO3 lead-free ceramics by sol-gel method

Abstract

The dielectric, piezoelectric, ferroelectric and pyroelectric properties of (Bi0.5Na0.5)1-xBaxTiO3 (x=0.00，0.04，0.06，0.08, 0.12) ceramics prepared by sol-gel method were investigated. It was found that all the samples in this experiment show improved piezoelectric properties,obtained by using this chemical method. For(Bi0.5Na0.5)0.94Ba0.06TiO3 ceramic, as its composition is near the morphotropic phase boundary (MPB), it shows the largest piezoelectric constant, d33=173×10-12C/N, which is about 40% improvement compared to the conventional processed ceramics in this system. In addition, from the ferroelectric and pyroelectric measurements, the remanent polarization Pr, coercive field Ec and depolarization temperature Td of the (Bi0.5Na0.5)0.94Ba0.06TiO3 ceramic were found to be 25μC/cm2, 28kV/cm, and 80℃, respectively.