Effect of ZnO nano-particulate modification on properties of PZT–BLT ceramics

This research was conducted to study the effect of ZnO nano-particulate modification on properties of Pb(Zr0.52Ti0.48)O3 (PZT)–(Bi3.25La0.75)Ti3O12 (BLT) ceramics prepared by a mixed-oxide solid-state sintering method. ZnO nano-particulate was added into PZT–BLT ceramics to obtain PZT–BLT/xZnO (x = 0, 0.1, 0.5 and 1.0 wt%). The PZT–BLT/xZnO ceramics were investigated in terms of phase, microstructure, physical, electrical, and mechanical properties. Tetragonality of PZT–BLT crystal structure tended to increase with increasing ZnO content. ZnO addition obviously increased the density of PZT–BLT ceramics while the grain size slightly decreased. Intergranular fracture mode was observed for pure PZT–BLT ceramic while the samples contained ZnO nano-particles showed a mixed-mode inter-/trans-granular fracture. Addition of ZnO also affected hardness and fracture toughness values. Addition of ZnO nano-particulate into PZT–BLT ceramics was found to improve room temperature dielectric constant but did not have a significant effect on ferroelectric properties. These observed results were expected to be caused by the behaviors similar to a donor-doped system.