Structure, ferroelectric and mechanical performance of polycrystalline gadolinium-doped lead lanthanum zirconate titanate ceramics

Gadolinium-doped lead lanthanum zirconate titanate (Pb0.94−xGdxLa0.06)(Zr0.52Ti0.48)O3: PLGZT ceramics with x= 0, 2, 4, 6, and 8% have been successfully fabricated using a sol-gel auto-combustion method. Pure perovskite PLGZT was acquired for the powder calcined at 850 °C for 3h. In addition, the manipulation of Gd³⁺-substituted PLZT on the microstructure, ferroelectric and mechanical properties was systematically considered. We have executed a deep structural analysis of X-ray powder diffraction data of PLGZT near the morphotropic phase boundary (MPB). The tetragonal and rhombohedral phases were found to coexist at room temperature. The remanent polarization Pr and coercive field Ec were calculated from the polarization hysteresis loops. The elastic constants were determined for the samples by ultrasonic wave propagation to determine the elastic behavior of the dopant on the PLZT matrix. The results showed that Gd doping in the A-site of the ABO3 perovskite system improves the hysteresis behavior. In the same manner, Gd doping was seen to enhance the mechanical properties.