摘要： Currently, there is an urgent need of extraordinary comprehensive pyroelectric materials for the wide application in detectors and energy harvesters. In this study, the (Pb1-1.5xLax)(Zr0.86Ti0.14)O3 (abbreviated as PLZT, x = 0.02, 0.03, 0.04 and 0.05) ceramics located in ferroelectric-antiferroelectric (FE-AFE) phase boundary were designed and synthesized by using conventional solid-state reaction method. The microstructures, phase structures, dielectric, ferroelectric, thermal depolarization and pyroelectric properties of the PLZT ceramics with different La content were investigated thoroughly. The XRD results show that the PLZT ceramics change from FE phase to AFE phase with increasing La content. The significant improvement of pyroelectric coefficient and figures of merit (FOMs) are achieved in the PLZT ceramics with the increase in La content because of the increased metastable ferroelectric phase under the application of electric field. The (Pb0.955La0.03)(Zr0.86Ti0.14)O3 (x = 0.03) ceramic exhibits not only high of and high depolarization temperature (Td) of 179 ℃ but also excellent FOMs with ???? = , ???? = , and ???? = 3 47 5 ???? ? . In addition, the highest of is achieved in (Pb0.94La0.04)(Zr0.86Ti0.14)O3 (x = 0.04) ceramic. These results demonstrate that the PLZT ceramics of x = 0.03 and 0.04 are promising candidates for pyroelectric applications.