Enhanced piezoelectric properties and constricted hysteresis behaviour in PZT ceramics induced by Li+–Al3+ ionic pairs

Abstract

Recently, we proposed a new approach (Li⁺–Al³⁺ ionic pairs doping) to enhance the piezoelectric properties of BaTiO₃ ceramic. Here we sequentially prove that Li⁺ and Al³⁺ can also enhance the piezoelectric properties of PbZr_0.52Ti_0.48O₃ (PZT) ceramic. The X-ray diffraction results demonstrate the optimized distribution of Li⁺–Al³⁺ ionic pairs parallel to the [001] direction in the doped ceramics, as same as the results in BaTiO₃-based ceramic. The doped ceramics exhibit constricted hysteresis loops, which is associated with the restoring force of Li⁺–Al³⁺ ionic pairs as a result of the Coulomb force between Li⁺ and Al³⁺ ions. The results show that the piezoelectric properties and corresponding temperature stability of the doped ceramics were enhanced significantly. The analysis and conclusion indicate that the piezoelectric mechanism coming from ionic pairs applies equally well to the PZT ceramic. Co-doping Li⁺ and Al³⁺ into the A-site is a preferable approach for the piezoelectric property enhancement of ABO₃ ferroelectric ceramics.