Tailored phase transition and electric properties of Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 ferroelectric ceramics by ZnO modification

Microstructure, phase transition and electric properties of Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 (PZTN 95/5) ferroelectric ceramics modified with x wt% ZnO additive (where x = 0, 0.1, 0.2, 0.3 and 0.4) were systematically investigated. It was found that ZnO modification brought out an improvement of densification and an increase in grain size of PZTN 95/5 ceramics. Results of dielectric and pyroelectric measurements demonstrated that, the low temperature rhombohedral-high temperature rhombohedral ferroelectric phase transition temperature (TLH) gradually decreased with increasing x to 0.2, while the Curie temperature (Tc) gradually increased. With further increasing ZnO content, however, TLH and TC almost showed no change. Additionally, the excellent ferroelectric, pyroelectric and piezoelectric properties were all achieved by less than 0.2 wt% ZnO modification. It is suggested that, due to superior room-temperature pyroelectric properties, the 0.2 wt% ZnO-modified PZTN 95/5 ceramics may be a promising material for applications in uncooled pyroelectric infrared detectors.